Dear Victor, Sanjay,

  what about using field isovists or visual graph analysis in a grid ?
By defining in a boolean grid you could control where potential
pedestrians could or cannot reside....

Maybe one has to extend axial analysis when it comes to open spaces in
the city like squares, parks etc to a hybrid form of isovist/axial
analysis.

best regards

 Bernhard

On 5/5-2004, at 10.16, Sanjay Rana wrote:

victor,

quite an interesting question. i suppose there must already exist a
formal
methodology to deal with this situation. I am personally of the opinion
that urban transport networks (e.g. roads, railways) already contain
some
degree of integration measures by virtue of their properties such as
speed,
capacity, safety, diretion (one-ways etc.), attraction (shops, garages,
scenic routes etc.). In my field of research (terrain analysis), I deal
with this situation in two ways:

I assign a certain amount of weights to features (e.g. if you want to
go
faster then you would take the motorway even if you could potentially
take
a "topological" short cut via a network of small roads. Therefore,
what I
am essentially suggesting is as follows:
Could you assign certain weights to the unused links (in fact all the
links) but still have them in your analysis for "topological
completeness"?

2. Secondly, please note, that this will also take you the edges of the
transport planning discipline (an active mailing list at
http://www.its.leeds.ac.uk/utsg/). In transport planning, such
"unconnected
networks" are sometimes assigned (linked) to a connected part of the
network (just pick any nearest road to the isolated path) which yields
a
completely connected network. But if the paths are blocked then thats a
different issue.

i hope this brain spill helps !

sanjay.

Bernhard Snizek
landscape architect MDL MSc

metascapes
Ravnsborggade 2,2
DK2200 Copenhagen N
Denmark

http://www.metascapes.dk
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