Dear Mr. Harrie fruyt van hertog:
On behalf of Mr. Peter
van der Vlist and Mr. Kees Landman, who are terrific techinicians of Transport
department, I would like to thank you for your concern about our research and I
will give a brief report about what we were doing on 18th Nov at
Krakeelpolderweg and Papsouwselaan, as you required.
In previous studies,
a model was developed to estimate travel time on urban road in very short time
intervals, the idea of which was to simulate the condition when GPS tools are
equipped on the vehicle as it reports the position and speed of that vehicle
every one minutes or shorter. In the model, it gave a probability algorithem to
calculate the possible delay for the vehicles that not only focus on specific
roads but aim to be generic for most road networks. As the model was tested and
modified by simulation software using generated data, we would like to know if
it works with real data. In a word, to test its validity.
To obtain data,
we chose to do road side observation with two synchronized cameras at a road
stretch with intersection in between. The reasons were that possibilities of
experiencing delays near intersections are large and mostly the largest ones
during trips; secondly we needed long observing distance and two cameras could
make it clearly and feasible to see how much time it takes for vehicles to pass
certain two spots before and after the intersection. One camera was installed on
the top of our van at 200 meters north of the intersection, and the other was
located at the parking lot of Fire department of Delft on its second floor. Then
we put red triangle marks at the road side to record the distance. The whole
observation took about 2 hours and we met quite a few kind people in between,
who were very interested in seeing us doing strange things, one of which I
believe was you or your colleague.
That was the whole summary. It was a
very successful observation. The research is still going on and may last for a
quite while.
Thank you for your time and Best
regards.
Thank you for your time and Best regards.
Nan
Zheng
Master student
Student assistant
Tel.
0648729051
Delft
University of Technology
Faculty of Civil Engineering
Department of
Transport &
Planning