Geoscience Reference
In-Depth Information
1 Introduction
1.1 Background
Since the inauguration of the Centre for 3D GeoInformation (3DGI) at Aalborg
University in 2001 one of the main goals in the centre have been to develop and
present a sustainable and feature rich platform to represent a 3D model of the world.
After initial years and several cycles of research prototyping, a novel concept of han-
dling object-oriented representations of geographic features on the server-side in
the exactly same form as on the client has emerged. The key reasoning behind this
concept based on the irst prototype was addressed in (Koláˇ
2006
). This meant a
paradigm shift in the core of the design and development. While traditional software
packages have predefined input and output data structures, the new design was based
on contents compiled to byte-code and executed directly by a virtual machine (VM).
This means every geographic feature may, if convenient, run as a little program.
Initially to be seen graphically on a computer monitor but equally importantly also
running algorithms in the background. These objects can be enabled for instance
to change position, or change form, communicate with other objects, or with real
objects connecting the virtual model to the real world. This approach has advantages
compared to traditional GIS software and is very suitable for 3D environments and
the sensor city concept (Senseable citylab—MIT
n.d.
). The content objects were
eventually called Geospatial Managed Objects (GMO). Running code in a VM as a
middle layer, is not new and was already introduced in 1966 (Richards
1969
; Rohl
and Feldman
1967
). Today the VM concept is known through Java Virtual Machine,
Microsoft's .Net, or Adobe Flash. Java Virtual Machine is used in our development
due to its versatility, huge open community and availability on most system plat-
forms (Bodum et al.
2005
; Kjems et al.
2009
; Kolar
2006
).
The first real attempt using GMO's in a city scale environment was the Energy
City Frederikshavn project in the years 2008-2011. The project aimed at an inter-
active city model where the user was able to identify and alter various energy con-
sumption data, and energy production data to try to optimize the total energy flow
in the city. The final product was meant as a tool for the public participation to
develop a plan for a sustainable city using 100 % green energy (Kjems and Wen
2011
; Kjems and Østergaard
2014
). The GMO concept made it straightforward to
connect 3D objects in the model with a user interface and further to an energy cal-
culation model server.
1.2 InfraWorld
Getting funding for a new GI system, build more or less from scratch and on new
ideas, is not easy. Some claim our approach has been tried before without any
success, and others don't believe in features build as objects using byte-code.
