VRVis-ComVis-Traces
VAST 2008 Challenge
Mini Challenge 4:
Evacuation Traces
Authors and Affiliations:
Wolfgang Freiler, VRVis Research
Center , Vienna , Austria
Kresimir Matković, VRVis Research Center , Vienna ,
Austria
Zoltan Konyha, VRVis Research Center, Vienna,
Austria,konyha@vrvis.at
Denis Gracanin, Virginia Tech., Blacksburg, USA, gracanin@vt.edu
Tomislav Lipic, University of Zagreb, Croatia tomislav.lipic@fer.hr
Ranko Miklin , University of Zagreb, Croatia r.miklin@gmail.com
Mario Beric, University
of Zagreb , Croatia
Student
team: NO
Tool(s):
We used
ComVis, a tool developed at VRVis
research center (http://www.vrvis.at). ComVis
reads the dataset from a csv file. Once read and stored user can select one of
more views (2D or 3D scatter plot, histogram, pie charts and myriad of
others)to represent attributes of the
dataset. Besides scalar attributes as usual in information visualization,
ComVis supports function graphs as attributes as well. All views are linked and
simple and composite brushing is supported. Sessions can be saved to avoid
re-reading of the dataset, to store view set-up, and to easily exchange
analysis steps with peers or create reports for end customers.
Two Page Summary: YES
VRVis-ComVis-Traces-Summarry.pdf
Video: YES
ANSWERS:
Traces-1
Where was the device set off?
Grid
cell number of where the device went off:
66x32
Short Answer:
We
think that the device was set off at position 66,32 because many people near this
spot stop moving shortly after the incident. We assume that these people are
dead or at least unconscious. Shortly before the incident, a person walks into
this room, waits from timestep 243 to 280, and walks out again. The grid cell
where this person paused could be the place of the bomb.
Traces-2
Identify potential suspects and/or witnesses to the event.
Note: Potential suspects
and/or witnesses are people who were near the area just prior to the explosion
and exhibit suspicious behavior
List
of RFID tag numbers :
21, 50, 18
Short Answer:
The
persons with the Ids listed above are potential suspects and/or witnesses to
the event, because they resided in the proximity of the bomb site. Person 21
also exhibits suspicious behaviour by waiting in the room next to the bomb
site, walking to the bomb site shortly before the incident, leaving it, before
it explodes, and waiting behind a corner for the explosion. This person also
does not leave the building immediately, but waits for person 1 to leave first,
because being the first one outside may be suspicious. Unless this was a
suicide attack, we think that 21 has placed the bomb, because the other two
witnesses die.
Traces-3
Identify any suspects and/or witnesses who managed to escape the building.
List
of RFID tag numbers :
21
Short Answer:
This
is the only main suspect we have. This person is the only one coming from the
bomb room that escapes.
Traces-4
Identify any casualties.
List of RFID tag numbers :
39, 47, 69, 78, 60, 65, 18, 50, 56, 76, 19, 36, 59 (moves back into the
building)
Short Answer:
Most
casualties occur near the bomb, and only our suspect is able to escape the
building. There is also a group of persons that die next to the exit on the upper
right. After some people leave the building, some others turn around and run
into the opposite direction. We do not exactly know why, but since the device
is not far away, we suspect fire or a collapsed wall has blocked the exit.
Person 36 does only move one step from timestep 243 to 244. This person either
died or lost his or her RFID Tag. Person 59 moves back into the building,
probably he or she forgot something important and tried to fetch it. From
timestep 693 on the person does not move any further, so he or she probably
died.
Traces-5
Describe the evacuation
Detailed Answer:
The
evacuation has been visualized using the PathView provided by ComVis. This
visualizationshows the positions and paths
of all persons in one image (with the plan of the hospital as a background
image).The view also provides an
animation mode, which shows the evacuation during time, to watch the evacuation
taking place. This view also supports brushing and linking, so we can highlight
interesting persons that have an unusually short path length (e.g. dead
people), ora large step size.
To
make it easier to recognize single persons in crowded areas, it is also
possible to show only the last few steps of each person. This reduced the
cluttering of the screen, and helps estimating walking speeds in still images - the longer a trailing line is, the faster a person is walking. It is also
possible to use transparency to find clusters in very crowded regions.
In
addition to the features described above, we can state, that the evacuation was
quite civilized, with the exception of the lower left corner. These persons
were not really endangered by the explosion, but this area was very crowded,
and some part of the hallway seems to be blocked. Therefore some people change
their mind and choose another route on the far left - some people even change
their mind twice. This is also the area where two people that were already near
the exit turn around and go back.
Figure
1: This is the situation shortly after the bomb has been placed (Timestep 300).
The red spot marks the bomb spot. The main suspect (orange) leaves the room,
before the bomb explodes, while the witnesses (green) do not seem to have
noticed the danger.
Figure
2: This image shows the situation during the evacuation (Timestep 588). While
the suspect (orange) has already escaped, the witnesses and other people in
this area (black) do not move anymore. We can assume, that they are dead. The
region on the upper right is very interesting. Some people (light green) manage
to escape, but from one moment on, people (red) do not escape through this
exit. They turn around, and stop moving soon. We think, that something (fire,
debris) must have blocked this way, and because these people do not run to
another exit, we can assume that they die too. On the lower left, people are
far away from the bomb, and therefore survive. However, evacuating this area
takes a long time, because half of the hallway seems to be blocked (dark green).
Some persons even turn around and try to find another way out (purple).
Figure
3: This image shows a screen section of ComVis during Analysis. The upper image
shows a Pathview depicting people near the bomb site. The dots represent their
current position (Timestep 487), the trailing lines show their last ten steps.
The persons painted in red have been brushed in the view below. This one shows
a time-series visualization of the path lengths of all people. Timesteps are
displayed in the x-dimension, path lengths in the y-dimension. Horizontal lines
represent people that do not move, rising lines represent movement. We have
brushed people with very short path lengths, all of them are near the bomb site
and died. The table below shows their IDs.