research in gis/giscience @ucd computer science gisystems and giscience: research issues...

Research in GIS/GIScienceResearch in GIS/GIScience

@UCD Computer Science@UCD Computer Science

GISystems and GIScience: GISystems and GIScience:

Research IssuesResearch Issues

• Multiresolution modelsMultiresolution models

• Automated map generalisationAutomated map generalisation

• Web-based and Mobile GISWeb-based and Mobile GIS

• Interoperable GISInteroperable GIS

MultiMultiresolution: Multiresolution: Multiple ple

Representations for Map DataRepresentations for Map Data

creek mouth

paper mill lakecreekriver

creek mouth

bridge

major road

paper mill lakecreekriver

intersection AB

minor road A minor road B

MultiMultiresolution: Multiresolution: Multiple ple

Representations for Map DataRepresentations for Map Data

creek mouth

bridge

major road

paper mill lakecreekriver

intersection AB

minor road A minor road B

MultiMultiresolution: Multiresolution: Multiple ple

Representations for Map DataRepresentations for Map Data

creek mouth

bridge

major road

paper mill lakecreekriver

intersection AB

minor road A minor road B

MultiMultiresolution: Multiresolution: Multiple ple

Representations for Map DataRepresentations for Map Data

Map Generalization

creek mouth

bridge

major road

paper mill lakecreekriver

intersection AB

minor road A minor road B

bridge

major road

paper mill lakeriver

minor road A

Extraction of a less detailed version of a mapExtraction of a less detailed version of a map

Generalization OperationsGeneralization Operations SelectionSelection

AggregationAggregation

CollapseCollapse

SymbolizationSymbolization

SimplificationSimplification

ExaggerationExaggeration

DisplacementDisplacement

H

Geometric Problems in Geometric Problems in Map GeneralizationMap Generalization

Simplification of linesSimplification of lines: empirical solutions and partial : empirical solutions and partial theoretical solutions [Douglas and Peucker 1973]theoretical solutions [Douglas and Peucker 1973]

Preservation of consistencyPreservation of consistency (no illegal overlap): need (no illegal overlap): need for a posteriori checksfor a posteriori checks

Automated map generalization: open problemAutomated map generalization: open problem

Multiple Representations for Multiple Representations for

Terrain DataTerrain Data

Multiple Representations for Multiple Representations for Terrain DataTerrain Data

Related Related problemsproblems::

simplification/refinement of the domain simplification/refinement of the domain subdivisionsubdivision

efficient data structuresefficient data structures

efficient algorithms for hierarchical query efficient algorithms for hierarchical query and reasoningand reasoning

A Multilevel TIN

MultiMultipleple Representations for Representations for TerrainsTerrains

• Efficient data structures including vertical links: Efficient data structures including vertical links: efficient hierarchical reasoning efficient hierarchical reasoning

• Algorithms for hierarchical spatial queries Algorithms for hierarchical spatial queries

• Algorithm for hierarchical overlay of plane Algorithm for hierarchical overlay of plane subdivisions subdivisions

• Visibility computation on hierarchical TINsVisibility computation on hierarchical TINs

Hierarchical Point LocationHierarchical Point Location

t0

t1

t2

t3

Web-Based GISWeb-Based GIS

Internet

RiversRoadsImagesSoils, Veg ...

Distributed DBs

Mobile GISMobile GIS

Issues: GIS and GPS integrationIssues: GIS and GPS integration

EfficientEfficient Transmission Transmission

Remote access through slow communication links: need Remote access through slow communication links: need for coarser versions of the dataset to perform preliminary for coarser versions of the dataset to perform preliminary analysisanalysis (progressive transmission) (progressive transmission)

Available: Available:

- interleaving/compression techniques for raster data- interleaving/compression techniques for raster data

- compression mechanisms for terrain data- compression mechanisms for terrain data

No implementation for map dataNo implementation for map data

Progressive TransmissionProgressive Transmission

Progressive Vector Transmission: Progressive Vector Transmission: A SolutionA Solution

BBased on a ased on a client-serverclient-server architecture: pre-compute a architecture: pre-compute a sequence of consistent representations at lower levels of sequence of consistent representations at lower levels of detail on the server site and transmit them in order of detail on the server site and transmit them in order of increasing detailincreasing detail

client

level 3level 4

server

full detail

level 1level 2level 3level 4

...

Multiresolution for Progressive Multiresolution for Progressive TransmissionTransmission

Client Server

Vector Maps Library

.....

Map 1

Map n

Vector map request

Transmit vector map

OK!

InteroperabilityInteroperability

OpenGIS consortium: OGCOpenGIS consortium: OGC

((www.opengis.org)) At the representation level: standard At the representation level: standard

model specificationsmodel specifications Format: GMLFormat: GML Processes Processes Web servers Web servers Mobile applicationsMobile applications

Geography Markup Geography Markup Language (GML)Language (GML)

XML-based language for exchanging spatial XML-based language for exchanging spatial data data

Geographic data content represented in text Geographic data content represented in text formform

XSLT (Extensible Stylesheet Language XSLT (Extensible Stylesheet Language Transformations) used to transform GML data Transformations) used to transform GML data into a suitable graphics format (e.g., SVG)into a suitable graphics format (e.g., SVG)

Scalable Vector Graphics Scalable Vector Graphics (SVG)(SVG)

Text-based vector data formatText-based vector data format Easily compressedEasily compressed SVG elements directly correspond to SVG elements directly correspond to

GML featuresGML features SVG viewer: PocketSVG viewer from SVG viewer: PocketSVG viewer from

CSIROCSIRO

1. 1. Knowledge Management Knowledge Management for for

Geo-Spatial ImageryGeo-Spatial Imagery

2.2.CoMPASS: Combining Mobile CoMPASS: Combining Mobile Personalised Personalised

Applications with Applications with Spatial Spatial ServicesServices

3.3. MEMS: Mobile MEMS: Mobile Environmental Environmental Management Management SystemSystem

PROJECTSPROJECTS

KnowledgeKnowledge Management for Management for Geo-Spatial ImageryGeo-Spatial Imagery (MaGIK) (MaGIK)

Sponsor:Sponsor: 2001 Enterprise Ireland 2001 Enterprise Ireland Research Innovation FundResearch Innovation Fund

Participants:Participants: M. Bertolotto, M. Bertolotto, D. Wilson, D. Wilson, Eoin McLoughlin, Eoin McLoughlin, Dympna O’SullivanDympna O’Sullivan

Sketch-based Geo-Spatial Sketch-based Geo-Spatial Image RetrievalImage Retrieval

Knowledge ManagementKnowledge Management

Image Database

Knowledge Base

MaGIK: on-going workMaGIK: on-going work

MaGIK Mobile: transferring MaGIK to the MaGIK Mobile: transferring MaGIK to the mobile platformmobile platform

GUI development: current 4GUI development: current 4thth year project year project

Sponsor:Sponsor: 2002 Enterprise Ireland 2002 Enterprise Ireland Advanced Technologies Research Advanced Technologies Research

ProgrammeProgramme

Participants:Participants: M. Bertolotto, M. Bertolotto, D. Wilson, D. Wilson, Julie Doyle, Julie Doyle, Dan Lynch, Dan Lynch, Joe Weakliam, Joe Weakliam, Helen Min ZhouHelen Min Zhou Eoin McAoidhEoin McAoidh

CoMPASS: Combining Mobile CoMPASS: Combining Mobile Personalised Applications with Personalised Applications with Spatial ServicesSpatial Services

Location-Based ServicesLocation-Based Services

Spatial ServicesSpatial Services

Associated text message

• Display maps

• Annotate maps

• Personalise maps

Technologies EmployedTechnologies Employed

Oracle Spatial database and application Oracle Spatial database and application serverserver

Java application programsJava application programs JDBCJDBC GML and SVGGML and SVG Pocket PC with GPS receiverPocket PC with GPS receiver Web clientWeb client

Web-based GUI: Web-based GUI: OpenMap OpenMap

Opensource GIS sw packageOpensource GIS sw package

Java-basedJava-based

Web-based GUI to Oracle Spatial DBWeb-based GUI to Oracle Spatial DB

OpenMap GUIOpenMap GUINavigation Panels

Message Panel

Tool Panel and Menu

Desktop watcher

Topology Property Dialog

Map Panel

Attribute Panel

OpenMap GUIOpenMap GUI

Mobile GUIMobile GUI GMLGML

SVGSVG

iPaq Pocket PCiPaq Pocket PC

Interface for Pocket PCInterface for Pocket PC

Sponsor:Sponsor: 2004 Enterprise Ireland 2004 Enterprise Ireland Innovation Partnership ProgrammeInnovation Partnership Programme

Participants:Participants: M. Bertolotto, M. Bertolotto, A. RizziniA. Rizzini

In collaboration withIn collaboration with: : Digital Media Centre, Digital Media Centre, DITDIT

E-Spatial Solutions Ltd.E-Spatial Solutions Ltd.

MEMS: MEMS: Mobile Environmental Mobile Environmental Management System Management System

Mobile Environmental Mobile Environmental Management System Management System

Deliver text-based field data sheets used by Deliver text-based field data sheets used by scientist of the Canadian Department of scientist of the Canadian Department of Fisheries and OceanFisheries and Ocean Plus Plus

additional multimedia informationadditional multimedia information

to a spatially-enabled DB with mobile to a spatially-enabled DB with mobile accessaccess

Digital Photos,

Maps, etc.

Oracle SpatialText-based

info

+