International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part B-YF. Istanbul 2004 
  
The Data Acquisition System integrates an Inertial 
Measurements Unit (IMU) receiver of the Wide Area 
Differential GPS (WADGPS), and a thermal camera. The 
WADGPS and IMU data are used to georeference the thermal 
images. The use of a thermal camera, which senses heat 
emitted in the form of infrared radiation, enables early detection 
and location of forest fires that could not be sensed by the 
human eye. The camera will also provide accurate images of 
the fire in reduced visibility due to haze, smoke or darkness. 
The real-time data acquisition system, designed to upload this 
data in real-time to the internet site, will sufficiently aid fire 
managers to effectively determine where to allocate resources 
and to quickly detect where hidden, smoldering fires are 
located. The accuracy obtained by this system is two to five 
meters and facilitates the acquisition of accurate reports on 
position, size and direction of the fire. For further information 
about this Data Acquisition System, see Wright and El-Sheimy, 
2003. 
The Control Center System houses the webpage. It has many 
responsibilities. The first of three main responsibilities is 
processing all information that is obtained by the Data 
Acquisition System. The second responsibility is performing 
the fire behavioral modeling functions. The last major 
responsibility is displaying the fire status monitoring 
information. More detailed information about these processes 
and functions will be given in the next section. 
The last sub-system, the Response System, enables the results 
of the Control Center System to be displayed to the user. This 
system allows the system user to view the results obtained from 
the Control Center System. 
All three sub-systems are linked through the Web based 
WMMS which organizes all functions of the Control Center 
System for use by the operator. A flow chart outlining the 
structure of the WMMS can be seen in Figure 2. 
  
Database Server 
  
  
Data Processing 
  
  
  
  
  
  
   
  
  
   
      
   
  
  
  
  
  
    
  
   
   
  
   
  
  
  
  
  
  
Results 
Query Data 
Upload Upload Data 
Data Get 
data 
Request 
Map/Image 
= via TCP/IP 
Get data = 
c 
z 
= 
= = Return Response 
= Upload v Map/Image System 
= data 3 via TCP/IP Client Viewer 
e e 
= T" Request Text (HTM L, 
8 via TCP/IP JavaScript, 
— Java Applet) 
Return Text 
via TCP/IP 
Apache Web Server 
  
  
  
  
  
  
Figure 2: Control Center System: Client/Server Communication 
The Database Server obtains the data from the Data Acquisition 
System and all data processed in the Control Center System can 
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be viewed by the client through the Response System. The 
WMMS has five main components, as shown in Figure 2 that 
allow the three main sub-systems to communicate seamlessly. 
These components are listed below: 
= Apache Web Server 
= Web MapServer 
= Hypertext Preprocessor Server (PHP) 
= Database Server 
= Transmission Control Protocol and Internet Protocol 
(TCP/IP) 
2.1 Apache Web Server 
The Apache Web Server is a computer platform that hosts the 
Web MapServer and the PHP server. The role of the Apache 
Server is to connect the client's personal computer to the stored 
wildfire data on the server via the MapServer and PHP servers. 
2.2 Web MapServer 
The Web MapServer is a public domain development 
environment from the University of Minnesota that is used for 
building spatially enabled Internet applications. This software 
works on any Linux, UNIX and Windows platform and has 
many GIS features which make it the most attractive option to 
use for the WMMS Webpage. MapServer also allows the 
clients to browse GIS data and to create geographic maps 
(Lime, 2003). It is responsible for all spatial data operations 
and publications in this system. 
MapServer works by configuring each application using a text 
file called a *mapfile". Anything associated with a particular 
application is defined in the mapfile as an object. In a single 
file there can be many objects used to build an entire interface, 
or just a single object used to build a simple legend or scale bar. 
To add to the functionality of the system, one can use and 
modify these objects through an HTML form. The program 
results are then run through a series of templates depending on 
the application (i.e.: data browse or feature queries) and the 
results are displayed to the user. 
2.3 PHP Server 
PHP is a general purpose scripting language that is particularly 
useful in Web development and can be easily embedded into 
HTML. The PHP server facilitates the transfer of image and 
textual data between the server and the client. It performs the 
searching techniques of the spatial and textual data. The user 
can thus access the newly published data processed by the 
control center through the Apache Web Server. However, since 
this web based fire modeling system is capable of publishing 
information in real-time, the data server must be accessed 
frequently. If textual, real-time data is transmitted, the PHP 
server can directly transfer the data from the database to the 
client via the TCP/IP protocol, which is explained later. If the 
data is a general image such as fire photos, the PHP server can 
automatically retrieve it from the database and pass to the 
client. 
2.4 Database Server 
Multiple types of data sets are used in this application such as 
text, spread sheets, general and georeferenced images, GIS data 
and GPS coordinates. This application uses the Standard Query 
Language (SQL) to organize the database. The SQL standard