GEOCOMPUTATIONS AND RELATED WEB SERVICES J. A. Rod Blais Dept. of - - PowerPoint PPT Presentation

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GEOCOMPUTATIONS AND RELATED WEB SERVICES J. A. Rod Blais Dept. of - - PowerPoint PPT Presentation

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GEOCOMPUTATIONS AND RELATED WEB SERVICES J. A. Rod Blais Dept. of Geomatics Engineering Pacific Institute for the Mathematical Sciences University of Calgary, Calgary, Alberta T2N 1N4 blais@ucalgary.ca www.ucalgary.ca/~blais OVERVIEW

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SLIDE 1

GEOCOMPUTATIONS AND RELATED WEB SERVICES

  • J. A. Rod Blais
  • Dept. of Geomatics Engineering

Pacific Institute for the Mathematical Sciences University of Calgary, Calgary, Alberta T2N 1N4

blais@ucalgary.ca www.ucalgary.ca/~blais

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SLIDE 2
  • Introduction
  • High Performance Computing (HPC)
  • Geodata, Metadata and Scientific Gateways
  • Web Services, Models and Frameworks
  • Virtual Globes: Earth, Virtual Earth & FreeEarth
  • Virtual Observatories (VOs) and HUBs
  • International Web Collaboration
  • Concluding Remarks

OVERVIEW

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SLIDE 3
  • Geocomputations often involve HPC
  • HPC grows exponentially but unfortunately,

data often grow faster in volume and complexity

  • Communication networks are ever expanding in global

coverage and capacity

  • Physically distributed data collections and computing

services need to be integrated into a virtual system for research, development and public relations

  • Virtual Globe and Observatory approaches provide novel
  • pportunuities for collaborative research and instructional

purposes, and future developments

INTRODUCTION

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SLIDE 4

Network and Block Adjustments NTS mapping: ~ 2000 stereomodels (7 par./model) NAD cdn networks: ~ 8000 stations ((φ, λ)/stn) NAD27 → NAD83: ~ 450 000 stns ((φ, λ)/stn) Spherical Harmonic Transforms (SHTs) SHT and SHT-1 in REAL*8 to ~ deg. & ord. 3800 Global grids: equiangular and near equiareal EGM08 ( http://earth-info.nima.mil/GandG/ ) Upgraded EGM96 using mostly Grace data Degrees ≤ 2190 and Orders ≤ 2159 ⇒ ~ 5 min. res’n

SOME HPC EXAMPLES

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GLOBAL SPHERICAL GRIDS

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2001 ANNUAL TEMPERATURE ANOMALY MAP

Source: http://www.msc.ec.gc.ca/acsd/publications/RMD_msc_report/policy/image_4b_large_e.html

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GEODATA and METADATA

INTERNATIONALLY:

  • World Data Centers: www.ngdc.noaa.gov
  • NASA, ESA: www.nesdis.noaa.gov
  • UNIDATA: www.unidata.ucar.edu
  • IAG Data Centers: www.iag-aig.org
  • Aviso for Altimetry: www.aviso.oceanobs.com

NATIONALLY:

  • NRCAN Geoscience Data Rep.: http://gdr.nrcan.gc.ca
  • Cdn Soil Information System: http://sis.agr.gc.ca/cansis
  • Cdn Water Information System: http://map.ns.ec.gc.ca/reseau/

LOCALLY:

  • University Digital Libraries (DEMs, maps, airphotos, imageries, …)
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SLIDE 8

i Geoscience Network http://www.geongrid.org i Marine Metadata Interoperability http://marinemetadata.org i NASA World Wind Geo http://worldwind.arc.nasa.gov i Global Environmental & Earth Science Information System http://genesis.jpl.nasa.gov i Semantic Web for Earth and Environmental Terminology http://sweet.jpl.nasa.gov

SCIENTIFIC GATEWAYS

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SLIDE 9

WEB SERVICES

A web service is some software available over a network with a formal description of how it is called and what it returns that a computer can understand. Note that web servers, ftp servers, database servers, etc., do not generally qualify as they lack the standardized descriptions of their inputs and outputs. Today, XML provides a language-neutral way for representing data and information. Remember that web services are meant for use by computers and not humans (unlike webpages in HTML, etc.)

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SLIDE 10

WEB SERVICE MODELS

RESOURCE-ORIENTED MODEL

A resource is anything that can have an idenfier e.g. a service.

SERVICE-ORIENTED MODEL

A service is something capable of performing a piece of coherent functionality e.g. actions performed by agents.

MESSAGE-ORIENTED MODEL

A message is the basic unit of data exchanged between agents.

POLICY-ORIENTED MODEL

A policy is a set of assertions expressing capabilities and constraints.

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SLIDE 11

WEB SERVICE FRAMEWORKS

LANGUAGE PACKAGE or LIBRARY Java Apache Axis ( http://ws.apache.org/axis ) Xfire ( http://xfire.codehaus.org ) C# .NET ( http://msdn2.microsoft.com/en-us/netframework/ ) Mono ( http://www.mono-project.com ) Perl SOAP::Lite ( http://www.soaplite.com ) Python SOAPPy/ZSI ( http://pywebsvcs.sourceforge.net ) C++/C gSOAP ( http://www.cs.fsu.edu/~engelen/soap.html ) Ruby soap4r ( http://dev.ctor.org/soap4r )

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VIRTUAL GLOBES

GOOGLETM EARTH ( http://earth.google.com )

  • Software from Keyhole Inc. (2004)
  • Multilingual and multi OS (Windows, Mac, Linux)
  • Three version levels (Free, $20/year, $400/year)
  • Ground resolutions: 15 cm … 15+ m
  • DEM data from NASA SRTM global coverage
  • 3D data in KML language for visualization
  • Google Street View available with version 4.3 (May ’07)
  • Errors re MSL (e.g. Death Valley: -86m instead of -420m)
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VIRTUAL GLOBES (continued)

Microsoft Virtual Earth ( http://www.microsoft.com/virtualearth/ )

  • Immersive imagery with city views in 3D
  • Cross-browser and improved printer support
  • Improved location functionality (traveling directions)
  • Global satellite imagery with uptodate map details
  • Online mapping and searching ( http://maps.live.com )
  • VE Interactive SDK ( http://dev.live.com/virtualearth/sdk/ )
  • VE ISDK provides hands-on, task-based demos of APIs
  • Designer Tools and Technologies for own website
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SLIDE 14

VIRTUAL GLOBES (continued)

Poly9 FreeEarth ( http://freeearth.poly9.com ):

  • Essentially no download with Adobe Flash Player 9
  • Cross-browser and multi OS (Windows, Mac, Linux)
  • Very light (main application ~ 300 KB)
  • Global satellite imagery with high resolutions for U.S. cities
  • All features exposed using simple JavaScript interface
  • Web Map Service (WMS) supported for GIS applications
  • Data encoded in XML (GeoRSS specs.) displayed easily
  • Imagery for other planets included
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SLIDE 17
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VIRTUAL OBSERVATORIES

Web environment for interactive

  • Browsing, searching and downloading data and tools
  • Integrating, synthesizing and analyzing new and legacy

datasets

  • Correlating, modeling and assimilating datasets
  • Prototyping and developing new tools and procedures

Examples

  • NVO in Astronomy ( http://us-vo.org ; http://ivoa.net )
  • VO in Geomagnetism ( http://mist.engin.umich.edu )
  • VO in IPY (Walker and Kulesa, at AGU Fall Meeting, 2006)
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SLIDE 19

NATIONAL VIRTUAL OBSERVATORY

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NVO APPLICATIONS

  • Web-based applications thru web browser
  • Downloaded applications run locally on

desktop or notebook local workstation, cluster or grid

  • Computationally intensive applications

initiated thru web browser carried out on some cluster or grid status info thru web browser visualization of results

  • Toolkits for building other applications

scripting languages such as IDL, Python, … programming languages such as Java, C++, …

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SLIDE 21

APPLICATIONS OF THE NVO

STAND-ALONE APPLICATIONS

  • VOPlot for plotting and visualizing the data
  • TOPCAT for graphical viewing table data
  • MIRAGE for image displaying and segmentation
  • ALADIN for image processing and visualization
  • SKYVIEW for viewing images and catalog services

WEB-BASED TOOLS

  • Datascope for accessing data holdings and related services
  • Registry for descriptions of data archives and services
  • … … …
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SLIDE 22
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SLIDE 23

Wilkinson Microwave Anisotropy Probe

Recent WMAP 5-year Results

Source: http://lambda.gsfc.nasa.gov/product/map/current

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SLIDE 24

HUBzero and nanoHUB

A ‘HUB’ is a web site built with many familiar open source packages: A Linux operating system running an Apache web server with

  • LDAP (Lightweight Directory Access Protocol) for user logins
  • PHP (Personal Home Page) for web scripting
  • Joomla (Open Source Content Management System)
  • MySQL database for storing content and usage statistics.

Web reference: http://www.hubzero.org Demo with nanoHUB: http://www.hubzero.org/demo.html

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WEB COLLABORATION

KEY WEB-BASED FEATURES:

  • Interactive Simulation Tools and Online Presentations
  • Mechanism for uploading New Resources
  • Tool Development Area and Usage Statistics
  • User Groups for Private Collaboration
  • Ratings and Citations and User Support Area
  • News and Events, and Feedback Mechanisms
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SLIDE 26

CONCLUDING REMARKS

  • Advanced Geocomputations often involve HPC
  • Web environments are more and more common for HPC
  • Virtual Globes allow interactive displaying of data
  • Virtual Globes are very useful with Satellite Imagery
  • Online globes like FreeEarth also allow presentation of

data entirely within a web portal

  • Virtual Observatories offer numerous possibilities for

web collaboration and development activities

  • Geoscience collaboration can really be international!
  • For more references:

The Virtual Earth: http://teachserv.earth.ox.ac.uk/resources/v_earth.html The Soft Earth: http://teachserv.earth.ox.ac.uk/resources/s_earth.html