Ontology Research for The

National Map

Dalia Varanka Research Geographer Center of Excellence for Geospatial Information Science Spatial Ontology Community of Practice Workshop October 17, 2008 U.S. Department of the Interior U.S. Geological Survey

Project Description

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Ontology for The National Map is a framework to more explicitly articulate detailed and shared information about U.S. topographic features

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A robust exchange of feature semantics enables greater information access for a diverse public

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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

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Integrate data from a variety of formats and platforms

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Enable natural language queries on features

Parts of this Presentation

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

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Semantic facets of queries

Topographic mapping

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

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A record of the changing American landscape

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National unity and identity These meanings serve as the semantic contexts for topographic feature ontology

Topographic maps and narratives

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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

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Scope: Science and Society

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Science is structured by its practitioners and broader social contexts

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The USGS is mission-driven to link science to society

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Common-term concepts

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For example: “The valley floor of the Grand Canyon,” “The spread of invasive species,” “Sea level rise”

Data Standards Ontology Software Gazetteer Name Feature Type Geoposition Unique ID GIS Database Thematic Layers Features Attributes Relations Boundary Generation Morphology Hypsography Elevation Hydrography Land Cover Land Cover Land Cover Non-Vegetative Cover Vegetative Cover Security Cadastral Division PLSS Events Natural Built Up Government Units Shaded Relief Landforms Geographic Domains GIS Layers of

The National Map

Contours Transportation Digital Orthoimagery Results Structures Boundaries

Transitional Areas Subclass with Instance Attribute from other Classes Unify existing stages of an ontology Feature lists Themes/domains Classification Gazetteer Crosswalks What we need DB interfaces Relations / axioms

URBAN AGRICULTURAL RANGELAND TRANSITIONAL AREAS BARREN LAND DRY SALT FLATS

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

20

th

-Century Topographic Mapping

A balance of mathematical, regional, and local mapping

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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

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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

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

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Best Practices Vector Data Model (The National Map)

Cover

Domains – Land Cover

FGDC Framework DLG-E (1988) DLG-F (1993) Data (1998) Non-vegetative surface cover Cover - Barren Land Cover - Built up Structure Cover - Built up - Complex Cover - Built up - Utility Cover - Built up - Network Built up Transportation Transportation Transportation-Base Transportation-Rail Transportation-Air Transportation-Transit Transportation-Roads Transportation Waterways Cover - Cultivated Cropland Cover - Vegetation Cover - Water Vegetative Surface Cover Hydrography Hydrography

The National Map

(2004) Cover Structures Transportation Hydrography

Domains - Surveys

FGDC Framework Data DLG-E DLG-F

The National Map

Government Unit Boundaries Division Division-Administrative Division-Boundary Division-Census Division-Hydrologic Unit Division-Land Parcel Division-Locale Division-Maritime Division-Political Division-Survey System Boundaries Cadastral Public Land Survey System Public Land Survey System Governmental Units

Domains – Earth Processes

DLG-E Ecosystem Morphology Geoposition DLG-F FGDC Framework Data Best Practices Data Model Named Landforms Hypsography Elevation Elevation Geodetic Control Digital Orthoimagery Digital Orthoimagery

Domains - Security

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Historical relation with defense mapping

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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

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

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

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forms Feature types, definitions, and domain expertise

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Production: surveys, instructions, memos, and compilation

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Gazetteer, particularly the Geographic Names Information System Volunteer geographic information Map reading events Content analysis of text concordances

Glossary

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Definitions

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A stream is a body of water, with a current, confined within a bed and stream banks.

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Concept conditions

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

Categorization

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Basic level

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

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

Other categories

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Degrees of membership

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No precise boundaries

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For example, wetlands

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Family resemblance

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Associated with super-classes

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For example, vegetation Generator

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Feature generates new features

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Glaciers generate cirques, till, moraine, kames

Syntax, with addition of names

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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

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What is Bluff Creek?

What is [name] [Name] [relation] [object] Bluff Creek is a stream.

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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

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Types and causes

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Regionalization (Hollows, Valleys, Bottoms)

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Borrowings (Playa, Mesa, Prairie) Geographic scale (River, Stream, Creek) Infrastructure change (Condo, Gated Community)

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Implications for query analysis

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Synonyms

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Variants Spatial cognition

Semantic context to enhance query functionality

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

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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)

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

Features and spatial relations

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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

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

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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: [email protected]