Participants: Edzer, Jan, Lubia and Karine

Title: Analyzing spatio-temporal phenomena from data: necessary representations and operations.

Different phenomena:

1. continuous physical phenomena (temperature, precipitation)
2. continuous vectors with a magnitude and direction (wind)
3. evolving objects (clouds)
4. moving objects: trajectories (animals), and their aggregates (flows; through a network? through free space?)
5. space-time point patterns (volcanic eruptions, scientific conferences), possibly marked

Topics to address:

1. (Karine: implementing/designing an algebra for a spatio-temporal database)
2. implementing a full algebra for spatio-temporal data analysis
3. web services to access spatio-temporal databases and web services for spatio-temporal data processing
4. dealing with uncertainty
5. usability of visualisation tools for uncertain spatio-temporal data
6. go beyond the time snapshot = animation analogy –> Q: What that means?, ST = time added to space.

What we want:

1. find/characterize/identify spatio-temporal patterns (change)
2. spatio-temporal patterns in streams/flows, understand spatio-temporal interactions

Publication 01) Survey of web services suitable for dealing with spatio-temporal data (access and processing) What means spatial-temporal data? : kinds of dynamic phenomena, the data that arrives from them, they are distribuited in different data sources (describe different data sources), examples for phenomena (animal and iceberg tracking) and for data types (fields,objects) , what kind of operations we need to deal with the data (trajectories, intersection, distance between trajectories, overlay). Search for existing ws specifications of different organizations such as OGC, ISO and others (?) that deal with this spatial-temporal data (SOS is for fixed sensors, WPS, WCS, OpenLS, Sensor Planning Service). Evaluate the existing web services by considering: which spatial-temporal data each of them deal with, how usable they are, how compliant are existing implementations, can they used for mobile sensors, for what purpose they are (accessing, processing).

!!!References!!!

Title: Survey of web services for spatio-temporal data

Abstract:

Spatial-temporal data is used to represent dynamic phenomena. These can be physical processes like temperature and precipitation or moving objects like trajectories of moving animals and their aggregates. The data derived from them are distributed in different data sources and formats. The operations on this data can be e.g. intersection of two objects or measuring distances between them.

The aim of this work is to clarify what kinds of data types we

Web service specifications for dealing with spatial data has been developed, such as Sensor Observation Service(SOS), Web Feature Service (WFS), Web Coverage Service (WCS), Web Processing Service (WPS), Open Location Service (OpenLS) and Sensor Planning Service (SPS). These can handle data at a certain time snapshot, but the question is if these web services can be used for analysing spatial-temporal data in a sense of a process in time. This paper should give an overview over existing webservice specification and evaluate them under certain aspects.

First the definition of spatial-temporal data should be discussed and

• TerraLib (database, elementary topological operations)
• TerraHS/Haskell (prototype implementation)
• PostGIS
• Secondo (database for moving objects), Aguila (visualisation)
• TerraME, PCRaster (environmental modelling)
• TerraView (wants to do animation)
• R, aRT
• OGC web services – 52N suite, …

1. web service (access and processing) specifications (Master thesis)
2. usability of visualisation of spatio-temporal data (Q: bachelor or master?)

- Q:Is goodness of fit a possible mobility measure proposal?