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Survey of Emerging IT Trends and Technologies Chaitan Baru Monday, 10 th Aug 1

Survey of Emerging IT Trends and Technologies

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Survey of Emerging IT Trends and Technologies. Chaitan Baru Monday, 10 th Aug. OUTLINE. Trends in data sharing And, Discovery/Search Trends in service-oriented architectures Trends in computing and data infrastructure The road ahead. Geoinformatics Use Cases. - PowerPoint PPT Presentation

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Page 1: Survey of Emerging IT Trends and Technologies

Survey of Emerging IT Trends and Technologies

Chaitan Baru

Monday, 10th Aug

1

Page 2: Survey of Emerging IT Trends and Technologies

OUTLINE

• Trends in data sharing– And, Discovery/Search

• Trends in service-oriented architectures

• Trends in computing and data infrastructure

• The road ahead

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Page 3: Survey of Emerging IT Trends and Technologies

Geoinformatics Use Cases• “…a use has access from a terminal to vast stores of

data of almost any kind, with the easy ability to visualize, analyze and model those data.”

• “For a given region (i.e. lat/long extent, plus depth), return a 3D structural model with accompanying geophysical parameters and geologic information, at a specified resolution”

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Implied IT Requirements

• Search and discovery of resources

• Integration of heterogeneous 3D / 4D Earth Science data

• Integration of data with tools

• Analysis and Visualization– Ability to feed data to tools, and analyze &

visualize model outputs

• (data-centric view…)

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Search and Discovery

• Searching “structured data”, i.e. metadata catalogs

5

Search

Structured metadatacatalogs

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Search and Discovery

• Searching “unstructured data”, i.e. the Web

6

Search

• Structured databases are a major component of the “Deep Web”

The Web

Page 7: Survey of Emerging IT Trends and Technologies

Combined Search and Discovery

7

Search

The WebStructured metadata

catalogs

Page 8: Survey of Emerging IT Trends and Technologies

Advanced Search• Proposed:

– Geoscience Knowledge System, GeoKnowSys

– Built using Yahoo Build Your Own Search (BOSS) service

• E.g. See wolframalpha.com

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Advanced Search: PaleoLit

• Research project at Dept of CS, CMU– Dr. Judith Gelernter and Prof. Jamie Carbonell

• Use ontologies to match search requests to related publications

• Demo…

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Page 10: Survey of Emerging IT Trends and Technologies

Informatics Issues: The Informatics Progression

IT Cyber

Infrastructure

Cyber Informatics

Core Informatics

Science Informatics,

aka

Xinformatics

Science, SBAs

Informatics

Courtesy: Prof. Peter Fox, RPI, CSIG’08

Page 11: Survey of Emerging IT Trends and Technologies

The Computer Science / Domain Science continuum

11

Computer IT Geoinformatics Domain DomainScience Standards Standards Standards ScienceTopics Topicse.g. Database e.g. ODBC, e.g. Ontologies, e.g. domain e.g. geologySystems, XML GeoSciML vocabulariesSemistructure data definitions (Geologic Time,

rock description,…)

Page 12: Survey of Emerging IT Trends and Technologies

The data interoperability onion

12

Social NetworksSemantics

SyntaxSystems

Social NetworksSemantics

SyntaxSystems

• System Interop– Approaches: e.g., ODBC, JDBC, Java, Web services, …

– Purview of: Computer Science

• Syntactic– Approaches: Schema standards

– Purview of: Standards organizations, domain science

repositories, data archives

• Semantic– Approaches: Controlled vocabularies, thesaurii, domain ontologies

– Purview of: Domain scientists

• Social Networks– Approaches: recommendation systems

– Purview of: social networking software (CS and domain science, data driven)

Page 13: Survey of Emerging IT Trends and Technologies

Software interoperability onion

13

Social NetworksSemantics

SyntaxSystems

• System Interop– Approaches: e.g., REST, Web services

• Syntactic– Approaches: e.g., SOAP, WSDL

• Semantic– Approaches: Controlled vocabularies, thesaurii, domain ontologies

– Purview of: Domain scientists

• Social Networks– Approaches: recommendation systems

– Purview of: social networking software

• Service orchestration via worflow systems

Page 14: Survey of Emerging IT Trends and Technologies

Geologic Map Integration Geologic Map Integration

Page 15: Survey of Emerging IT Trends and Technologies

Data Mediation• Dealing with heterogeneities in (distributed) data sources

– Data may be in different “administrative domains” Manage authentication

– Data schemas may be different among sources

– Terminologies may be different among sources

– Terminologies may be different among sources and user

– Software infrastructure (“stack”) may be different

• Solve the problem with “middleware”– Layers of software between the original application and the end user

• Mediator– Middleware that bridges across heterogeneities without requiring sources

to change

Page 16: Survey of Emerging IT Trends and Technologies

AZNM CO

UT

NV

ID

MT MT

WYShapefile(ESRI)

PostGIS

Oracle

Windows Linux iMac

DB2 SRB

GML

• Operating system• File storage• Database schemas• Data Semantics

Heterogeneities

A Data Integration Example: Geologic Maps

Page 17: Survey of Emerging IT Trends and Technologies

FORMATIONUNIT_NAMEROCK_TYPEERASYSTEMSERIESLITH

ROCK_TYPEPERIOD

AZNM CO

UT

NV

ID

MT MT

WYWMS

WMS

WMS

WMS

WMS

• Integrated presentation• Uniform syntactical structure• Uniform spatial definition

Advantages

• Each resource may use a different schema• Difficult to build a a uniform query interface for multiple resources.

Problems

Adopting WMS/WFS: Can provide Syntactic Integration

Page 18: Survey of Emerging IT Trends and Technologies

GeoSciML: Can Provide Schema Integration

AZNM CO

UT

NV

ID

MT MT

WYGeoSciML

GeoSciML

GeoSciML

GeoSciML

GeoSciML

• Integrated schema• Partial integrated semantics

Advantages

• Each resource may use different vocabulary and semantic model.

Problem

British Rock Classification

Multi-hierarchical Rock Classification

Page 19: Survey of Emerging IT Trends and Technologies

Semantic Mediation with GeoSciML

NMCO

British Rock Classification

Multi-hierarchical Rock

Classification

GeoSciML

Application Ontology

Semantic Mapping

Mappings may also be needed between the data and the application ontology

E.g., say, mapping 240 mya to Mesozoic

Page 20: Survey of Emerging IT Trends and Technologies

Query Rewriting:Example: A Rock Classification

Ontology

Composition

Genesis

Fabric

Texture

Page 21: Survey of Emerging IT Trends and Technologies

Query: Concept Expansion

Composition

Concept expansion:Concept expansion:• what else to look for when what else to look for when user asks for ‘Mafic’user asks for ‘Mafic’

Page 22: Survey of Emerging IT Trends and Technologies

Query: Concept Generalization

Composition

Generalization:Generalization:• finding data that are ‘like’ finding data that are ‘like’ X and YX and Y

Page 23: Survey of Emerging IT Trends and Technologies

Ontology-based Geologic Map Integration: Implemented in GEON

Show formations where AGE = ‘Paleozic’

(without age ontology)

Show formations where AGE = ‘Paleozic’

(without age ontology)

Show formations where AGE = ‘Paleozic’

(with age ontology)

Show formations where AGE = ‘Paleozic’

(with age ontology)

+/- a few hundred million years

domainknowledge

domainknowledge

Knowledge

repres

entation

Geologic Age

ONTOLO

GY

NevadaNevada

Page 24: Survey of Emerging IT Trends and Technologies

<odal:NamedIndividuals odal:id="RockSample" odal:database="VTDatabase"> <odal:Class odal:resource="http://geon.vt.edu#RockSample" /> <odal:Table>Samples</odal:Table> <odal:Table>RockTexture</odal:Table> <odal:Table>RockGeoChemistry</odal:Table> <odal:Table>ModalData</odal:Table> <odal:Table>MineralChemistry</odal:Table> <odal:Table>Images</odal:Table> <odal:Column>ssID</odal:Column> </odal:NamedIndividuals>

GUIgenerate to ODAL

processor

The values in the column ssID of the tables Samples, RockTexture, RockGeoChemistry, ModalData,MineralChemistry and Images represent instances of RockSample

•ODAL: Ontological Database Annotation Language• Create a partial model of ontologies from database

ODAL, SOQL, and Data Integration Carts™

Page 25: Survey of Emerging IT Trends and Technologies

SOQL: Simple Ontology Query LanguageQuery single or many resources

• via ontologies (i.e., high level logical views)• independent of physical representation (i.e. schemas)

RockSample Location

ValueWithUnit float

location

hasSiO2

valuelat long

unit

string

SELECT X.location.*; FROM RockSample X WHERE X.location.lat > 60 AND X.location.long > 100 AND X.hasSiO2.value < 30 AND X.hasSiO2.unit =‘weightPercetage’

GUI

generateto SOQLprocessor

Page 26: Survey of Emerging IT Trends and Technologies

Issues in sharing data: Primary vs secondary (derived)

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Collect Data

Process and Visualize

Share Results

Share data

Share intermediateresults

Page 27: Survey of Emerging IT Trends and Technologies

Sources of Data• Distributed data collections

– By individual PIs

– “Informal” sharing, e.g. via social network

– “Formal” sharing, e.g. via submission to community data archives / databases

• Centralized data collections– E.g. via a large project (standardized protocols)

– By agencies (internal protocols)

• Metadata to the rescue– Data description standards

– Process description standards (workflows)

• State Surveys and USGS are major sources

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Page 28: Survey of Emerging IT Trends and Technologies

Major Interoperability Efforts

• OneGeology.org– International initiative of

geological surveys to create dynamic geological map data available via the web.

• US Geoscience Information Network (US GIN)– Led by Lee Allison, AZGS

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Federating Metadata Catalogs

• Local vs Community “View”– Individual data providers may choose to “export” a

community view

• Direct access to the source may still provide more “rich” access to data

• Federated Catalogs– The Geosciences Information Network, GIN approach

– Adopt standards for catalog content (ISO) and implementation (CSW)

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Page 30: Survey of Emerging IT Trends and Technologies

Interoperation between GEON and GEO GRID

• Implement CSW interfaces– Collaboration with the NSF PRAGMA project (Pacific Rim Assembly for Grid

Middleware Applications)

600 scenes/day

Storage

GeogridCatalog

Catalog Service

Web

WMS Server

WMS URL

SRB

GEON Catalog

Catalog Service

Web Adapter

WMS Server

WMS URL

ADN

CSWREQUEST

RESPONSE

CSW Composite

Service

CSWREQUEST

RESPONSE RESPONSE

GEON GEO Grid

Page 31: Survey of Emerging IT Trends and Technologies

Integration & Visualization of 3D/4D data

–Derived 3D volumetric model–Multiple isosurfaces with different transparencies–Slices through the volume–Variable gridding: data typically has lower resolution at greater depths

–2D surface data: Topography (“2.5D”) Satellite imagery, street maps, geologic maps, fault lines, and other derived features etc.

–Bore hole or well data and point observations.

“For a given region (i.e. lat/long extent, plus depth), return a 3D structural model with accompanying physical parameters of density, seismic velocities, geochemistry, and geologic ages, using a cell size of 10km”

Page 32: Survey of Emerging IT Trends and Technologies

OpenEarth Framework Goals

Geoscience Integration:

• Data types - topography, imagery, bore hole samples, velocity models from seismic tomography, gravity measurements, simulation results…

• Data coordinate spaces and dimensionality - 2D and 3D spatial representations and 4D that covers the range of

geologic processes (EQ cycle to deep time).

Page 33: Survey of Emerging IT Trends and Technologies

OpenEarth Framework GoalsStructural Integration:

• Data formats – shapefiles, NetCDF, GeoTIFF, and other formal and defacto standards.

• Data models - 2D and 3D geometry to semantically richer models of features and relationships between those features.

• Data delivery methods & Storage Schemes- local files to database queries, web services (WMS, WFS) and services for new data types (large tomographic volumes, etc.).

Page 34: Survey of Emerging IT Trends and Technologies

OEF Philosophy

• OEF focused on integrating data spanning the geosciences.

• Open software architecture and corresponding software that can properly access, manipulate and visualize the integrated data.

• Open source to provide the necessary flexibility for academic research and to provide a flexible test bed for new data models and visualization ideas.

Page 35: Survey of Emerging IT Trends and Technologies

OEF Architecture

Page 36: Survey of Emerging IT Trends and Technologies

OEF ArchitectureData Integration Services:

– Designed to support rapid visualization of integrated datasets

– operations to grid data, resample it at multiple resolutions and subdivide data to better support progressive changes to the display as the user pans and zooms

Page 37: Survey of Emerging IT Trends and Technologies

OEF ArchitectureVisualization Tools:

– Run on the user's computer, dynamically query spatial and temporal data from the OEF services

– Uses 3D graphics hardware for fast display

– Open architecture supports multiple visualization tools authored throughout the community (e.g GEON IDV)

– New viz capabilities developed as necessary

Page 38: Survey of Emerging IT Trends and Technologies

OEF Visualization

Page 39: Survey of Emerging IT Trends and Technologies

The software services stackExample: GEON

Pushing down the service interface

Compute nodes Disk Storage

Page 40: Survey of Emerging IT Trends and Technologies

Compute nodes Disk Storage

Software as a Service:At different levels of software

SaaS

PaaS

• Software as a Service: SaaS– E.g., Google Apps, Salesforce.com, SAP, …

• Infrastructure as a Service, IaaS– E.g., Amazon EC2, …

• Platform as a Service, PaaS

IaaS

Page 41: Survey of Emerging IT Trends and Technologies

The evolving computational architecture

• Mainframe computers (institutional computing)

• Minicomputers (departmental computing)

• Workstations (laboratory computing)

• Laptops (personal computing)

• …back to the future..??

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Page 42: Survey of Emerging IT Trends and Technologies

Cloud Computing: A meeting of trends

Data Volumes

Price/performanceof computing

platformsCost of

Ownership

Page 43: Survey of Emerging IT Trends and Technologies

Cloud Computing Origins

• Cloud computing: Many definitions– Here’s one: Use of remote data centers to manage scalable, reliable, on-

demand access to applications

• Origins– Goes back to the need by Web search engines to inexpensively process all

the pages on the Web

– Done by creating a grid of datacenters and processing data in parallel across them

– Development of a parallel data programming environment by Google: MapReduce

• Data + cloud computing– what about remote centers for scalable, reliable, on-demand access to

data?

Page 44: Survey of Emerging IT Trends and Technologies

Cloud Computing

• A different pricing model– No upfront cost of acquisition. Rent don’t buy.

• Can access 1000’s of processors / disks– Scalability– “Elastic computing”

• A different model for dealing with system failures– Retry, loose consistency, …

Page 45: Survey of Emerging IT Trends and Technologies

Cloud computing for data

• Data as a service: what is the abstraction for storage?– Table, Blob, Queue

– …??

• Describing characteristics of the data– Metadata about storage to specify policies to be applied

– Security, reliability, performance, etc

• Scaling to meet application needs– Large configurations

– Dealing with virtualization

– New failure models• Retry, loose consistency

Page 46: Survey of Emerging IT Trends and Technologies

Storage as a Service• Amazon S3: An example

– Charges for Storage, Data Transfer, and Requests (e.g. PUT, COPY, POST, LIST, GET)

• Issues– Bandwidth to storage

– Quality of Service

– Storage Elasticity

– Privacy / security

• Standardization efforts– Storage Networking Industry Assocation (SNIA) Technical Working Group (TWG)

on Cloud Storage has just started

• Important Issues– Metadata for storage

– Scaling up to large dataset sizes

Page 47: Survey of Emerging IT Trends and Technologies

The two sides of Cloud Computing

• Large distributed infrastructure– “Everything is in the cloud”

– Interesting as a proposition for the IT operations of an enterprise

– Cloud companies would like to reach deep into enterprise IT

– “Our business is not the entrenched data centers in current large organizations, but the new companies…”

• Large-scale infrastructure in the Datacenter– Seeding the cloud

– Shared-nothing parallelism

– Data on the cheap…a la Google

Page 48: Survey of Emerging IT Trends and Technologies

The NSF Cluster Exploratory (CluE) Program

• Google-IBM-NSF Cluster– Well over a thousand processors

• When fully built out, will comprise approximately 1,600 processors

– Terabytes of memory

– Hundreds of terabytes of storage

• Open source software– Linux and Apache Hadoop

• IBM Tivoli– System management, monitoring and dynamic resource provisioning

• A platform for “apples-to-apples” comparisons– Can reserve time on nodes for exclusive access

Page 49: Survey of Emerging IT Trends and Technologies

Our CluE Project

• Project (PI: Baru; co-PI: Krishnan)– Performance Evaluation of On-Demand Provisioning Strategies for Data

Intensive Applications

• Investigate hybrid software model– Database system / Hadoop system

– Some parts of the application require features provided by a DBMS• Transactional capability, full SQL support

– Other parts of the application can exploit Hadoop model• Very large data sets

• Data parallel processing

• Loose consistency models

• Price / performance is an issue– Including energy costs

Page 50: Survey of Emerging IT Trends and Technologies

San Andreas Fault LiDAR Dataset:

Data Access Patterns• B4 Dataset

Page 51: Survey of Emerging IT Trends and Technologies

Experiments

• “On-demand” database vs Hadoop

• SQL vs Hadoop

• Energy consumption as a factor in price/performance

• Platforms to be used

• Google-IBM cluster

• OpenCirrus testbed

• Triton resource

Page 52: Survey of Emerging IT Trends and Technologies

The Road Ahead• Advanced search engines

– Search structured and unstructured data

– Deal with display of heterogeneous results

– Show provenance of data

• Sophisticated tools for 3D and 4D data integration– Combination of “server-side” processing and caching and

client-side interaction and visualization

• Service-oriented architecture– Applications and IT infrastructure available as services

– Perhaps some of them in “the Cloud”

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Dealing with very large data

• Either the data can be partitioned into segments and processed in parallel– Shared-nothing parallelism

• Or not– Shared memory systems

Page 55: Survey of Emerging IT Trends and Technologies

Parallel Processing of Large Data

D

P

M

P P P P

Shared Memory

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Network

Shared Nothing

D

P

M

D

P P P P

M M M M

D D D

Page 57: Survey of Emerging IT Trends and Technologies

Shared Nothing

Dataset

Partitioning Strategy

D

P P P P

M M M M

D D DD

M

P

Page 58: Survey of Emerging IT Trends and Technologies

Data partitioning strategies• Round-robin

– Equal distribution across nodes by data volume

• Hash– all data with the same

key value go to same node

• Range– all data within a

range of values go to the same node Dataset

Partitioning Strategy

D

P P P P

M M M M

D D DD

M

P

Page 59: Survey of Emerging IT Trends and Technologies

MapReduce / Hadoop• Programming environment for very large scale

data processing

• Managing task executions and data transfers in a shared nothing environment– MapReduce: Infrastructure to support data scatter / gather

– Distributed data repository (“file system”)• Google File System (GFS)

• Hadoop Distributed File System (HDFS)

– Round-robin partitioning of data

• MapReduce– Google’s proprietary implementation

• Hadoop– Apache, open source implementation

Page 60: Survey of Emerging IT Trends and Technologies

• Hadoop vs databaseMapReduce execution

Page 61: Survey of Emerging IT Trends and Technologies

MapReduce vs Database• Database

– Partition “base tables” into N partitions

– Intermediate data can be “re-partitioned”

– Intermediate data can be combined

– Well-defined algebra for data manipulation (SQL)

• MapReduce / Hadoop– Partition input data file into M splits

– Intermediate data are re-hashed

– Intermediate data can be “combined”

– Java programs

• Cost of dynamic vs static partitioning– Run time costs

– Storage costs

• Optimal partitioning– Query and Workload dependent

– How to measure any deviations from the optimal?

– When to repartition?

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USGS Role in USGS Role in GeoinformaticsGeoinformatics

Fundamental: Develop, maintain, make accessible:Fundamental: Develop, maintain, make accessible: Long-term national and regional geologic, Long-term national and regional geologic,

hydrologic, biologic, and geographic databaseshydrologic, biologic, and geographic databases Earth and planetary imagery Earth and planetary imagery Open-source models of the complex natural Open-source models of the complex natural

systems and human interaction with that systemsystems and human interaction with that system Physical collections of earth materials, biologic Physical collections of earth materials, biologic

materials, reference standards, geophysical materials, reference standards, geophysical recordings, paper records.recordings, paper records.

National geologic, biologic, hydrologic, and National geologic, biologic, hydrologic, and geographic monitoring systems geographic monitoring systems

Standards of practice for the geologic, Standards of practice for the geologic, hydrologic, biologic, and geographic scienceshydrologic, biologic, and geographic sciences

Source: Presentation by Dr. Linda Gundersen, USGS, at Geoinformatics 2007, San Diego, CA.

Page 63: Survey of Emerging IT Trends and Technologies

USGS Role in USGS Role in GeoinfomaticsGeoinfomatics

All activities: Data creation, modeling, All activities: Data creation, modeling, monitoring, collections, standards etc. monitoring, collections, standards etc. Must be done in cooperation and Must be done in cooperation and collaboration with the public and collaboration with the public and governmental, academic, and private governmental, academic, and private sector partners and stakeholders.sector partners and stakeholders.

A critical USGS role: A critical USGS role: facilitate bringing communities facilitate bringing communities

together!together!Source: Presentation by Dr. Linda Gundersen, USGS, at Geoinformatics

2007, San Diego, CA.

Page 64: Survey of Emerging IT Trends and Technologies

Data Collections versus Data Collections versus Communities of PracticeCommunities of Practice

Geoinformatics must evolve beyond the Geoinformatics must evolve beyond the accumulation of data, models, and standards accumulation of data, models, and standards to become the framework for a to become the framework for a community community of practiceof practice in the natural sciences. in the natural sciences.

Etienne Wegner and Jean Lave coined the Etienne Wegner and Jean Lave coined the term and developed the learning theory of term and developed the learning theory of communities of practice – that we learn not communities of practice – that we learn not only as individuals but as communities. By only as individuals but as communities. By engaging in communities of practice we engaging in communities of practice we increase our capacity and innovation as well increase our capacity and innovation as well as leverage our support for areas of interest. as leverage our support for areas of interest.

Source: Presentation by Dr. Linda Gundersen, USGS, at Geoinformatics 2007, San Diego, CA.

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Creativity, Learning, and Creativity, Learning, and InnovationInnovation

A community of practice is not merely a A community of practice is not merely a community with a common interest. But community with a common interest. But are practitioners who are practitioners who share experiences share experiences and learn from each otherand learn from each other. They develop a . They develop a shared repertoireshared repertoire of resources: experiences, of resources: experiences, stories, tools, vocabularies, ways of stories, tools, vocabularies, ways of addressing recurring problems. This takes addressing recurring problems. This takes time and sustained interactiontime and sustained interaction. Standards . Standards of practice and reference materials will of practice and reference materials will grow out of this. grow out of this. But the critical benefits But the critical benefits include: creating and sustaining include: creating and sustaining knowledge, leveraging of resources, and knowledge, leveraging of resources, and rapid learning and innovation.rapid learning and innovation.

Source: Presentation by Dr. Linda Gundersen, USGS, at Geoinformatics 2007, San Diego, CA.

Page 66: Survey of Emerging IT Trends and Technologies

1000’s of National and 1000’s of National and Regional DatabasesRegional Databases

The National Map – topographic, The National Map – topographic, elevation, orthoimagery, elevation, orthoimagery, transportation hydrography etc.transportation hydrography etc.

Geospatial One Stop-portalGeospatial One Stop-portal MRDATA – Mineral Resources and MRDATA – Mineral Resources and

Related DataRelated Data The National Geologic Map Database The National Geologic Map Database

stnadardized community collection of stnadardized community collection of geologic mappinggeologic mapping

National Water Information System - National Water Information System - NWISWebNWISWeb

National Geochemical Survey National Geochemical Survey Database (PLUTO, NURE)Database (PLUTO, NURE)

National Geophysical Database National Geophysical Database (aeromag, gravity, aerorad)(aeromag, gravity, aerorad)

Earthquake CatalogsEarthquake Catalogs North American Breeding Bird SurveyNorth American Breeding Bird Survey National Vegetation/speciation mapsNational Vegetation/speciation maps National Oil and Gas AssessmentNational Oil and Gas Assessment National Coal Quality InventoryNational Coal Quality Inventory

Source: Presentation by Dr. Linda Gundersen, USGS, at Geoinformatics 2007, San Diego, CA.