Loading...
 
ESA > Join & Share > Technology Projects > ProxSe Project
Print

ProxSe Project

ProxSE

Proximity Search Engine 

Contractor (Mapflow)

Context
 
The common objective of the Open Geospatial Consortium, Inc. (OGC) and ISO/TC 211 is to define transparent access to heterogeneous geo-data and geo-processing resources in a networked environment. For that they provide a comprehensive suite of open interface specifications that enable developers to write interoperating components that provide these capabilities. Using these specifications, the Geographic Information System offers the possibility to access distributed data. By making geographic data sharing effective, user requests progressively evolved towards the provision of services adapted to their use rather then simple data access.

Currently Web Map and Feature Services permit to answer queries on which map images or features are available over a certain area within a specified time range. They do not permit to easily relate objects at the same time in space and time, answering queries like "all ships close to an oil spill" or "burned areas identified within X days from fires". However, come custom developments exist, but they seem to be limited to local systems and furthermore the problem becomes much more complex when data is geographically distributed.

 
Objectives 
 
The objective of this project is to create a open source code layer on top of distributed servers for identifying, through standard interfaces and commands, objects close in space and time.
Examples to be supported are:
  • Identification of all ships position that wihin a defined time period and area or interest are close (or overlap) in space (within user defined minimum and maximum distance) and time (within user defined minimum and maximum time difference) to oil spills (n this case the time difference is expected to be minimal or zero)
  • Identification of all ships trajectory that within a defined time period and area of interest are close (or overlap) in space (within user defined minimum and maximum distance) and time (within user defined minimum and maximum time difference) to oil spills (n this case the time difference is expected to be minimal or zero)
  • Identification of all burned areas that within a defined time period and area of interest are close (or overlap) in space (within user defined minimum and maximum distance) and time (within user defined minimum and maximum time difference) to fires (n this case the time difference can be also of some days)
Architecture
 
The ProxSE project is organized as follows:
  • Analyse related (current and forthcoming) Geospatial Web Services standards (Web Feature Service(WFS) 1.2, Simple WFS, Sensor Observation Service etc.)
  • Define and implement an improved Service Prototype
  • Define, implement and validate an open source Prototype Application
How it works
 
A simple web based interface will allow users to access the functionality of the Service Prototype through the Prototype Application:
- Insert and delete data from the system
- Query spatio-temporal data using both spatial and temporal filters
- Enter searches based on any of the temporal relationships as defined in Allen's Interval Algebra:
  • Before
  • After
  • Begins
  • End
  • During
  • Equals
  • Contains
  • Overlaps
  • Meets
  • Overlappedby
  • MetByBgunBy
  • EndedBy
and the spatial filters
  • Contains
  • Disjoint
  • Equals
  • Intersect
  • Overlaps
  • touches
  • Within
and have the results of this query displayed on a map.
 
Output
 
The ProxSE project will follow the traditional waterfall development model:
Part 1: Identification of the user requirement
Part 2: Definition of the software requirements, design of the architecture and definition of the interfaces
Part 3: Definition of the use cases
Part 4: Design and implementation of the Service Prototype and the Prototype Application
Part 5: Integration of the software
Part 6: System testing and validation
Part 7: User evaluation and final presentation.

 


Contributors to this page:
.

Page last modified on Tuesday 08 of March 2011 14:10:00 CET by .