U.S. Department of the InteriorU.S. Geological Survey

Ontology Research for The National Map

Dalia VarankaDalia VarankaResearch GeographerResearch GeographerCenter of Excellence for Geospatial Information ScienceCenter of Excellence for Geospatial Information Science

Spatial Ontology Community of Practice WorkshopSpatial Ontology Community of Practice Workshop

October 17, 2008October 17, 2008

Project Description

Ontology for The National Map is a framework to more explicitly articulate detailed and shared information about U.S. topographic features A robust exchange of feature semantics enables greater

information access for a diverse public Richer data models based on ontology will increase

potential data applications

National Research Council recommends to establish a research priority to explore use of geographic feature ontologies for geographic features to enable information discovery Integrate data from a variety of formats and platforms Enable natural language queries on features

Parts of this Presentation

Background Topographic mapping and narrative Narrative as an approach to restore ontology

semantics Semantic facets of queries

Topographic mapping

Base map – an empty container Surface landscape features at local scale Navigational device Natural resource and urban development

A record of the changing American landscape

National unity and identity

These meanings serve as the semantic contexts for topographic feature ontology

Topographic maps and narratives

Topography as a type of temporal, narrative experience of the land (Lukermann 1961; Curry 2002)

American topographic landscape as the stage of our domestic experience

Routine activities, narratives, and symbols associated with places

Topographic map as the information storage device for that experience

Interact with the map via narratives and symbols

Application of the ontology to The National Map

Scope: Science and Society Science is structured by its practitioners and

broader social contexts The USGS is mission-driven to link science to

society

Common-term concepts For example: “The valley floor of the Grand

Canyon,” “The spread of invasive species,” “Sea- level rise”

Ontology Software

GazetteerGeoposition

Name

Features Attributes Relations

Vegetative Cover

Hydrography

Security

Hypsography Non-Vegetative Cover

DivisionLand Cover

Natural Built Up

Morphology

Shaded Relief

ElevationBoundary

Generation

GIS Database

Data Standards Thematic Layers

Cadastral PLSS

Boundaries

Government Units

Contours StructuresTransportation

Digital Orthoimagery

Results

Unique ID

Feature Type

Events

Landforms

Land CoverLand Cover

Geographic Domains

GIS Layers of The National Map

URBAN

AGRICULTURAL

RANGELAND

BARREN LAND

DRY SALT FLATS

TRANSITIONAL AREAS

Transitional Areas Subclass with Instance Attribute from other Classes

Taken from: Anderson and others, 1976, A Land Use and Land Cover Classification System for Use with Remote Sensing Data, USGS

Unify existing stages of an ontology

Feature lists

Themes/domains

Classification

Gazetteer

Crosswalks

What we need

DB interfaces

Relations / axioms

20th-Century Topographic Mapping

A balance of mathematical, regional, and local mapping

Combined photogrammetric (air photo) and planetable (field) methods of surveying

Were focused on the 15 or 7.5 minute quadrangle, not government units

Topographic Instructions were general for regional implementation with state partner needs

Memos for verbal mediation and modifying ideas

National Databases

Transition to a single national database strengthened centralized standardization of feature lists

Field offices vied for national center status Feature lists served various functions, such

as mapping, digital computation, and data interoperability, not just regional character

Specifics communicated via metadata, not two-way discourse

Based on governmental unit

Objects: Feature and Code Lists

DLG Best Practices

Cable/Pipeline Site Util_Line

Dam Site Util_Point

Substation Util_Structure

Pipeline Regulation Station Util_Area

Feature List Standards Comparisons

Spatial Data Transfer Standard (SDTS) Digital Line Graph-Enhanced (DLG-E) Digital Line Graph-Feature (DLG-F) Federal Geographic Data Committee (FGDC)

Framework Best Practices Vector Data Model

(The National Map)

DLG-E (1988) DLG-F (1993)FGDC Framework

Data (1998)The National Map

(2004)

Cover Cover

Cover - Barren LandNon-vegetative surface cover

Cover - Built up - Structure Built up Structures

Cover - Built up - Complex

Cover - Built up - Utility

Cover - Built up - Network Transportation Transportation Transportation

Transportation-Base

Transportation-Rail

Transportation-Air

Transportation-Transit

Transportation-Roads

Transportation-Waterways

Cover - Cultivated Cropland

Cover - Vegetation Vegetative Surface Cover

Cover - Water Hydrography Hydrography Hydrography

Domains – Land Cover

DLG-E DLG-FFGDC Framework

Data The National Map

Division BoundariesGovernment Unit Boundaries Governmental Units

Division-Administrative

Division-Boundary

Division-Census

Division-Hydrologic Unit

Division-Land Parcel Cadastral

Division-Locale

Division-Maritime

Division-Political

Division-Survey System

Public Land Survey System

Public Land Survey System

Domains - Surveys

Domains – Earth Processes

DLG-E DLG-FFGDC Framework

DataBest Practices

Data Model

Ecosystem

Morphology Named Landforms Elevation Elevation

Hypsography

Geoposition Geodetic Control

Digital Orthoimagery Digital Orthoimagery

Domains - Security

Historical relation with defense mapping

New emphasis on event-based, hazard management

Ops_IncidentLine

Ops_AccessLine

Ops_SearchRescueLine

Ops_SearchRescuePoint

Ops_IncidentPoint

Ops_AccessPoint

Ops_EmergencyFacility

Ops_IncidentArea

Ops_AccessArea

Ops_SearchRescueArea

Ops_AlertArea

Ops_ResourceAssignment

Ops_DamageAssessment

Assumptions so far

The working hypothesis is that we share a common-term vocabulary within the topographic map, but statements and queries are personalized and vary;

The tendency to move feature types to data model implementation may be narrowing our discourse about topography; and

Syntactic variance of query statements reflects the narrative of topographical experience; feature lists are better than code lists.

Approach

Base the analysis of feature content and syntactic structures on various narrative forms Feature types, definitions, and domain expertise Production: surveys, instructions, memos, and

compilation Gazetteer, particularly the Geographic Names

Information System Volunteer geographic information Map reading events Content analysis of text concordances

Glossary

Definitions A stream is a body of water, with a current,

confined within a bed and stream banks.

Concept conditions …is a body of water …has a current, a source, a mouth [is] confined within a bed and stream banks

Categorization

Basic level Appear between super- and sub-classes Have an associated action that comes to mind Have the most attributes Have the most whole-part structures

For example, road (driving) and river (flows)

Other categories

Family resemblance Associated with super-classes

For example, vegetation

Degrees of membership No precise boundaries

For example, wetlands

Generator Feature generates new features

Glaciers generate cirques, till, moraine, kames

Syntax, with addition of names

Geographic Name Report Description

Bluff Creek is a stream about 10 miles long heading in [sec./twp./range] flowing generally SE to the Leaf River in [sec./twp./range] about 5 miles southeast of Bluffington.

[name] [subject] [modifier_length] [start_location] [event] [direction] [end_junction] [end_location] [proximity]

Queries

What is Bluff Creek? What is [name]

[Name] [relation] [object]

Bluff Creek is a stream.

Where is Bluff Creek? Where is [name][start-location] [event-direction] [end-location] [proximity]

Headed in [sec./twp./range] Bluff Creek flows generally SE to the Leaf River in [sec./twp./range] about 5 miles southeast of Bluffington.

Ontology to Database Interface

Semantic similarity

Types and causes Regionalization (Hollows, Valleys, Bottoms) Borrowings (Playa, Mesa, Prairie) Geographic scale (River, Stream, Creek) Infrastructure change (Condo, Gated Community)

Implications for query analysis Synonyms Variants Spatial cognition

Semantic context to enhance query functionality

Features with indeterminate boundaries carry semantic ambiguity in definition, name, and recognition.

By relating landform features with indeterminate boundaries to elevation, a geographical or environmental context, the identification, extent, and naming of these features is defined despite linguistic or spatial perspective ambiguity.

Elevation (context) and Landform (feature)

Landform term Glossary term definition Coded criteria applied to elevation context Landform feature extraction

Features and spatial relations

Absolute location: gazetteer coordinates Topological location: Query the topology

rather than the feature as the primary subject

‘What is “near” the “lake?”

Summary: work in progress

Work in progress includes the conceptual design and ontology software development of categorization, relation, attributes.

Current research includes integrating the ontology software to USGS databases.

Contact

Dalia Varanka

Center of Excellence for Geospatial Information Science

Tel: 573-308-3897

Email: dvaranka@usgs.gov