Syntactic and semantic based approaches for Geoinformation Management - Dr. Surya S. Dhurba
- 1. Syntactic and Semantic-based approaches for Geoinformation Management Surya S. Durbha, PhD Associate Professor CSRE, IITB
- 2. Outline Background Standards-based Geospatial Approaches Sensor Web enablement of GeoSensors Need for Semantic approaches for integrating Geoinformation
- 3. Earth Observation from Multiple Vantage Points Multiple vantage points for Earth observation leads to widespread real time sensors and multiple archives of imagery and other datasets.
- 4. Keywords Geographical Information Systems Spatial Data, Vector, Raster Standards, information sharing OGC, Web Services, Interoperability Data Integration, Decision Support Geoinformatics Information Systems, Computer Science, Remote Sensing
- 5. Overview and Definition of GIS It brings together the ideas developed in various fields Focus of GIS activity centers around Hardware and software Information processing Applications
- 6. Environmental Attributes Map Layer Geology Hazard Areas Existing Land Use Noise Contours Floodplain Soils Vegetation Surficial Hydrology EI Study Areas Planning Study Index Reference
- 8. What Does A GIS Do? GIS can answer the following questions: 1. Location - What is at a given location? 2. Condition - Where does it occur? 3. Routing - What is the best way? 4. Trend - What has changed? 5. Pattern - What is the pattern? 6. Modeling - What happens if ?
- 9. Who needs access to coordinated geographic information? Land Records Adjudication Disaster Response Transportation Management Water, gas & electric planning Public Protection Defense Natural Resource Management Telecommunications Infrastructure Economic Development Civic Entrepreneurs Regional Stewards
- 11. 11 Client1 Client2 Client3 Server1 Server2 Server3 Client1 Server1 Server2 Server3 Client2 Non-interoperable Systems Connected Systems Geospatial Interoperability Geospatial Interoperability enables disparate and geographically distributed systems/information sources to use and exchange geospatial information Standards-driven geospatial web services provide interoperability and the ability to harmonize varied data sources. Interoperability enables to build cost effective systems, and helps to reduce redundancy in an organizations spatial infrastructure. Geospatial Web services is the de facto way to access and publish: Data, Services and metadata Spatial Data Infrastructures (SDI) are adopting these standards to facilitate interoperability with other SDI systems world wide.
- 12. Understanding the context for information discovery Need information about roads that are NOT flooded for rapid evacuation Web service that provides data about traffic and road condition based on several parameters Context 1 Context 2 Disaster Management …Context N
- 13. 13 Vision: Develops standards for geospatial web services Mission: A world in which everyone benefits from geographic information and services made available across any network, application, or platform The Open Geospatial Consortium (OGC) Need to integrate Geospatial data from heterogeneous data sources. Incompatibilities in structural, syntactical and semantic representation hinders interoperability. Lack of interoperability impedes development of integrated decision support systems, reduces the ability to respond to time critical events and in general provide the right information at the right time.
- 14. Web Services
- 15. Services, Interfaces and Operations Service - distinct part of the functionality that is provided by an entity through interfaces, Interface - named set of operations that characterize the behavior of an entity Operation - transformation or query that an object may be called to execute. Each operation has a name and a list of parameters. Service Operatio n Interface provides requires has "A service is a function that is well-defined, self-contained, and does not depend on the context or state of other services.”-Source: Web Services and Service-Oriented Architecture: The Savvy Manager's guide
- 16. Web Services A service registry is a directory of services available in an SOA system. It contains the physical location of services, versions and validity periods of services, service documentation, and policies. A service registry is one of the main building blocks of an SOA architecture.
- 17. SOA and XML SOA needs a common platform to base its infrastructure. XML is the foundation for virtually all web services standards, such as: XML schema, SOAP, Web Services Description Language (WSDL), and Universal Description, Discovery, and Integration (UDDI). XML resolves the challenge of working with different data formats in different applications across multiple platforms. XML has the benefit of ease of representation, being text-based, flexible, and extensible by nature.
- 18. Representational State Transfer(REST) o REST Web service follows four basic design principles: • Use HTTP methods explicitly. • Be stateless. • Expose directory structure-like URIs. • Transfer XML, JavaScript Object Notation (JSON), or both. The acronym REST stands for Representational State Transfer, this basically means that each unique URL is a representation of some object. In RESTful web services, the emphasis is on simple point- to-point communication over HTTP using XML You can get the contents of that object using an HTTP GET, to delete it, you then might use a POST, PUT, or DELETE to modify the object
- 19. GET/POST operations (REST) GET is a read-only operation. It can be repeated without affecting the state of the resource and can be cached POST is a read-write operation and may change the state of the resource and provoke side effects on the server. To create a resource on the server, use POST. To retrieve a resource, use GET. To change the state of a resource or to update it, use PUT. To remove or delete a resource, use DELETE.
- 20. Copyright (c) 2009 Opengeospatial Consortium OGC Web Services (OWS) Web Map Service (WMS) Web Feature Service (WFS) Web Coverage Service (WCS) Catalogue (CSW) Geography Markup Language (GML) OGC KML Others… Relevant to geospatial information applications: Critical Infrastructure, Emergency Management, Weather, Climate, Homeland Security, Defense & Intelligence, Oceans Science, others Web Map Server Web Coverage Server Web Feature Server George Percival, OGC Standards: an Overview Tutorial,2010
- 22. OGC Web Services Copyright © 2010, Open Geospatial Consortium, Inc. What can you do? GetCapabilities Here… read this. <Service> … </Service> <Capabilitiess> … </Capabilitie> <Layer> … </Layer> Capabilities Document Great! Give me data Get Map, Feature, or Coverage Data Here you are…. George Percival, OGC Standards: an Overview Tutorial,2010
- 23. 23 1. Data Discovery: Provide search and discovery to geospatial data and services 1. Data Visualization – Provide visualization images of the actual geospatial data 1. Data Access – Provides access to the actual geospatial data Web based services with a focus on geospatial information Geospatial Web Services
- 24. 24 User Applications Data Discovery CatalogCatalogCatalogs Geospatial Web Services Features Content Repositories Coverages Data Visualization Data Access Geospatial Web Services Types
- 25. Web Map Server Web Coverage Server Web Feature Server With OGC web services, an analyst or operator can dynamically access that data which is relevant to the task at hand, directly from the authoritative data steward, using a variety of tools.
- 26. Multiple overlaid maps One GetMap request: Borders Elevation Cloud Cover Cities Web Map Service (WMS) can get multiple maps
- 27. Standards based Web Services Applications e.g., Community Water Quality, Climate Change Monitoring, Site Assessment Services e.g., Water Quality Index Service Gazetteer service, Web Map Service Data e.g., water quality, quantity, topographic, thematic, imagery, toponymy, metadata Users Other Applications For Example…A community website which calculates water quality for a given community Uses Gazetteer service, Water Quality Index Service Web Map Service based on Geographical Names, Road network features Base maps
- 40. The problem CSIRO. WaterML2.0 overview Need flow data! I’ll ring Don, he Has Data *RING RING* Hi Don, I need some upper Derwent flow readings for my geochemical model. Any ideas? Don Hmm, I’ve got one site. I’ll send it through… 10 minutes… To: Jack 01/02/09, 3.2, 3, 1 01/02/09, 3.1, 3, 1 10 minutes…*RING RING* Ok. Got the data. Where is the site located? Oh, it’s at laughing jack bridge. Coordinates? Ummm. (papers shuffle) 147.123 -41.588 What reference system?? I think it’s GDA94 Ok. What sensor is used? It’s calculated from the stream gauge reading using a rating curve..Oh…how accurate is that? Umm...... DON? Hydro Jack *CLICK*
- 41. © 2007, Open Geospatial Consortium Interoperability Institute, Inc. Sensor Webs Webcam Environmental Monitor Industrial Process Monitor Stored Sensor Data Traffic Monitoring Satellite-borne Imaging Device Airborne Imaging Device Health Monitor Strain Gauge Temp Sensor – Sensors connected to and discoverable on the Web – Sensors have position & generate observations – Sensor descriptions available – Services to task and access sensors – Local, regional, national scalability Automobile As Sensor Probe
- 43. Sensor Web Vision I Sensors will be web accessible Sensors and sensor data will be discoverable Sensors will be self-describing to humans and software (using a standard encoding) Most sensor observations will be easily accessible in real time over the web
- 44. Sensor Web Vision II Standardized web services will exist for accessing sensor information and sensor observations Sensor systems will be capable of real-time mining of observations to find phenomena of immediate interest Sensor systems will be capable of issuing alerts based on observations, as well as be able to respond to alerts issued by other sensors
- 45. Sensor Web Vision III Software will be capable of on-demand geolocation and processing of observations from a newly-discovered sensor without a priori knowledge of that sensor system Sensors, simulations, and models will be capable of being configured and tasked through standard, common web interfaces Sensors and sensor networks will be able to act on their own (i.e. be autonomous)
- 46. Building Blocks: OGC SWE Registries & Dictionaries Sensor Description Language Phenomenon Description Language Services Observation Tasking Alerting Analysis SensorML O&M SOS SPS SAS WNS CS-W
- 48. Forest Fire Monitoring Jirka, S., Broring, A., Stasch, C.: Applying OGC Sensor Web Enablement to Risk Monitoring ¨ and Disaster Management. In: GSDI 11 World Conference, Rotterdam, Netherlands (June 2009)
- 49. Flood Monitoring and Prediction Source: Nataliia Kussul, Andrii Shelestov, Sergii Skaku THE SENSOR WEB TESTBED FOR FLOOD MONITORING AND PREDICTION
- 50. Water Quality Monitoring Jirka, S., Broring, A., Stasch, C.: Applying OGC Sensor Web Enablement to Risk Monitoring ¨ and Disaster Management. In: GSDI 11 World Conference, Rotterdam, Netherlands (June 2009)
- 52. IMpacting Research, INnovation and Technology’ (IMPRINT-India)
- 53. IMpacting Research, INnovation and Technology’ (IMPRINT-India)
- 54. IMpacting Research, INnovation and Technology’ (IMPRINT-India)
- 55. Discovery and access mechanisms for sensors and data within and across wireless sensor networks (WSNs)_ Development of standardized catalogue or sensors registry, for querying services, individual sensors, and spatio-temporal data. Ability to retrieve the lineage of sensor observations (Data provenance) Automatic sensor installation, configuration and operation (GC) Integrating diverse sensors into observation systems Integrating data from sensor networks into the National Spatial Data Infrastructure (NSDI) Event based-notification and alerts Ability to support on-demand processing of sensor observations accessed from disparate and sensor networks belonging to multiple domains (e.g. Water and environment) Development of remotely taskable sensor systems (GC) IMpacting Research, INnovation and Technology’ (IMPRINT-India)
- 57. Geosemantic Web
- 58. Semantic Interoperability “Although standards from bodies like the OGC provide the basis for syntactic interoperability the usability of information that is created in one context is often of limited use in another context because of insufficient means for meaningful interpretation” (Bernard, Einspanier, Haubrock, et al., 2003),
- 60. Semantic Web Semantic means meaning Meaning enables a more effective use of the underlying data. Meaning is often absent from most information sources, requires users or complex programming instructions to supply it. Semantics give a keyword symbol useful meaning through the establishment of relationships. ( e.g. Building, Bank, etc)
- 61. Joshua Lieberman - European Geoinformatics Workshop 2007 ©Traverse Technologies. Which airfields within 80 miles of Banda Aceh support C5A aircraft, i.e. have a runway length >= 12000 ft? equivalence or subsumption based on based on Domain Ontology Ontological (DL) description of the query concept Query concept ID Name Airp_Ident ICAO Elev Type 1 Greenville US01357 KZ 00541 A 2 Festus Mem US05536 KZ 00433 A Ontological (DL) description of the application concept “Dafif_Airport” Application Ontology ConceptJohn Smith Hybrid Ontology Approach Logical Reasoning Ontologies for Enhanced GI Discovery
- 62. Joshua Lieberman - European Geoinformatics Workshop 2007 ©Traverse Technologies. “Typical” Geospatial Query (Intelligence / Logistics Domain) “Which airfields within 500 miles of Kandahar support C5A aircraft?” Aero Feature or Geo Feature? Buffer or proximity? Statutory or Nautical? Straight-line or driving? Coordinate system? Afghanistan? Centroid or outline? What does this mean to a GIS ? Feature property or non-spatial information?
- 63. “Typical” Analyst Query: “Which hospitals within 30 mins of Alpine, CA provide burn treatment?” Buffer or proximity? Driving or Flying? Road Closures? Where is this? Centroid or outline? Feature Reference Type? What does this mean? Definition?
- 64. • We need to associate a number of factors, including hospital type and facilities – its accessibility after a disaster – and the staff available • The query needs to be structured based on Concepts & Relationships that can be retrieved and then customized for the specific query. • Using this approach, a listing of the hospitals capable of dealing with large number of burn cases is returned to the user and information associated with the query retrieved. A “Simple” Knowledge Query Which hospitals within 30 mins of Alpine, CA provide burn treatment?”
- 65. Semantic heterogeneities Sea surface Temperature Ocean Temperature GCMD (Global Change Master Directory) Wind_Speed DODS Wind_SpeedWind_Speed_ve (Vector averaged wind speed) Wind_Speed_sc (scalar averaged wind speed) NDBC Wind Speed Water Temperature
- 66. Example Ontology for Natural Disasters University of Georgia Dept. of Computer Science
- 67. Example Ontology for Volcanoes University of Georgia Dept. of Computer Science
- 68. Semantic Conflicts GoMoos buoy data served through Distributed Oceanographic Data System (DODS) NDBC
- 69. A concept called WaterTemperature
- 70. A-Box and T-Box SPARQL A-Box Query SPARQL is a protocol and query language for semantic web data sources. Based on matching graph patterns. PREFIX rdfs:<http://www.w3.org/2000/01/rdf- scheme#> PREFIX bu:<http://cosem.erc.msstate.edu/ontologies/cosemo nt.owl#> SELECT * FROM <file:/c:/ontologies/cosemont.owl> WHERE { ?s bu:hasStationID ?g. ?s bu:waterTemperature ?WaterTemperature. ?g bu:latitude ?la. ?g bu:longitude ?lo FILTER(?WaterTemperature>20) }
- 71. Example SPARQL Query (Scenario: “Find devices that can produce certain output variables”)
- 74. Heterogeneities in Classification Systems The problem is finding the right data that matches a given criteria. Classification systems exist in several domains and also unique to different countries. Information is normally disseminated through classification Land Cover International Geosphere Biosphere Programme (IGBP) United States Geological Survey (USGS) Olson Global Ecosystems (OGE) Simple Biosphere model (SiB) Simple Biosphere 2 (SiB2) Biosphere Atmosphere Transfer Scheme (BATS) Soils natural resources conservation service (NRCS) Canadian soil classification system Unified soil classification system Wetlands U.S. Fish and wildlife service USGS wet land classification Ramsar classification system Cowardian system
- 75. International Geosphere Biosphere Programme (IGBP) Simple Biosphere model (SiB) Semantic conflicts between classification systems (IGBP and SiB)
- 76. International Geosphere Biosphere Programme(IGBP) Ontology Defined concept (mixed forest) formulated by defining necessary and sufficient conditions in a IGBP ontology
- 77. Thank you
- 78. Spatial Decision Support Systems (SDSS)
- 79. Information Systems are of two types Transaction processing systems o Emphasis on recording, updating and retrieving as per the occurrence of operations o Operate in on-line or batch mode and follows well defined procedures Example : Banking and Airline Reservation Systems Decision Support System o Emphasis on manipulation, analysis and particularly modeling to support decision makers. o Used in market analysis, resources planning, defence etc. GIS belongs to the second type!
- 80. http://proceedings.esri.com/library/userconf/proc97/proc97/to500/pap486 /p4861.gif
- 81. 81 Applications Many Applications of network routing Examples: Online Map service, phone service, transportation navigation service Identification of frequent routes Crime Analysis Identification of congested routes Network Planning
- 82. Spatial Decision Support Many times decisions have to be taken by administrators o Cannot satisfy all stakeholders o Cannot find money for entire needs o Cannot complete the task within a given time o Cannot protect environment while carrying out development projects Environment related issues are most controversial, requiring most spatial inputs
- 83. Use of GIS for environmental/resources management applications includes: 1. Data management 2. Data Assessment 3. Modelling and spatial analysis 4. Management and decision support Applications 1 thru 3 culminate in 4... the end use? Spatial Decision Support
- 84. Application or decision support? An application may end at any point o Spatial / attribute data creation end at 1 o descriptive/mapping exercise may end at 2 o predictive modelling exercise may end at 3 o BUT they must start at 1 and work through these stages in sequence The ultimate end application must be decision making (i.e. management) and use in support of decisions made
- 85. Example: Environmental Management Aims of environmental management: o to prevent environmental deterioration and degradation o to promote sustainable use of the environment o to prevent over use or exploitation of natural resources o to preserve environmental diversity Objectives of environmental management: o to control the environment and/or our influences upon the environment via direct or indirect action o i.e. putting environmental science to work!
- 86. Decision making or support? Decision making vs decision support o GIS can provide certain tools for assisting in the decision making process i.e. maps/displays as means of visualising the problem overlays as means of defining relationships modelling as means of predicting outcomes etc.
- 87. …the answer GIS functions on their own are NOT decision making tools... o (i.e. they only ASSIST in the decision making process) o ...therefore, GIS is not a decision making tool, it is a decision SUPPORT tool
- 88. Decision making Decision making: o a decision is a choice between alternatives to meet specific objectives o the alternatives may represent: different courses of action different hypotheses different use of a geographical entity etc.
- 89. Decision objectives Objectives are governed by management goals and in turn determine the range of alternatives o e.g. identify areas of high risk in soil erosion example in order to address the goal of preventing soil erosion o resulting alternatives may be different maps representing different management plans Process, governing the way decisions between alternatives are made, is the “decision rule”
- 90. Applications of Local Operations Soils: Revised Universal Soil Loss Equation (RUSLE) uses six environmental factors in the equation: A=R K L S C P A=average soil loss R=rainfall-runoff erosivity factor K=soil erodibility factor L=slope length factor S=slope steepness factor C=crop management factor P=support practice factor Each factor can be prepared as as an input raster. o Multiply the rasters in a local operation to produce the output raster of average soil loss. http://www.scotland.gov.uk/Resource/Img/47121/0020519.jpg
- 91. Definition of a DSS In general terms, DSS are: o computer-based systems o dedicated to a restricted but well defined area of application o systems incorporating modelling and analysis with data and database management systems o systems which do not make decisions, but facilitate logistics of decision making process o interactive systems that help decision maker carry out a decision research o providers of custom-built information o providers of user-friendly GUI with short response times
- 92. Developing Spatial DSS The role of GIS? o GIS is an INCREDIBLY USEFUL tool o SDSS retains the general characteristics of basic DSS but in addition they include: spatial data input capabilities storage of complex structures common in spatial data analytical techniques unique to spatial data cartographic output An agricultural SDSS might be comprised of: o climatic and economic models o GIS software o spatial data
- 94. SDSS Components SDBMS - locational, topological and thematic data types to support cartographic display, spatial query, analytical modeling MBMS - model base management system to support statistical and numerical models which stores models instead of data Each model may be a small piece of code to solve a part of an algorithm
- 95. SDSS Components Knowledge based reasoning, image processing may be part of the MBMS Graphical and tabular report generators 2-d and 3-d displays Bar charts, pie-charts, scatter plots, line plots, ... Application specific plots and reports
- 97. Credit: Environmental Simulation Center, 2004. 3D visualization is used to show community members how a proposed development would change the landscape.