Lucas, this is often good advice, but there are also clear cases when
we need a more complex representation. For example, in rapidly
growing cities we often find smaller scale streets parallel to and
accessible from major through roads, with the smaller scale street
having many more connection to the local grid, and often working as a
local centre of activity accessible both from the local grid and from
the through route. Other cases approximate this kind of pattern and
call, I think, for the more complex representation - even if
continuity maps are being used (which might be a very interesting
idea). - Bill
>Dear Chengke Liu,
>
>What axial maps capture the "potential" of the grid, which is related
>to the hierarchical structure of the street network. The actual
>physical properties (width, number of lanes) and constraints
>(directions, traffic flows, traffic lights) are not taken in account.
>However, we expect that most cases present a clear correspondence, for
>instance, long lines tend to have more lanes and larger width than
>short lines.
>
>Therefore I would recommend representing the urban grid in the most
>simplified way, reducing all lanes to a single axial line unless when
>there is a clear physical barrier spliting the lanes, such as a canal
>or a wall.
>
>I had similar problems when applying this kind of representation for
>vehicular movements. You may find some help at:
>
>Figueiredo, L., Amorim, L., 2004, "Continuity lines: aggregating axial
>lines to predict vehicular movement patterns"
>http://mindwalk.com.br/papers/
>
>
>Regards,
>Lucas Figueiredo
>
>On 05/01/07, Chengke LIU <[log in to unmask]> wrote:
>>Dear all,
>>
>>Thanks Professor Bill Hiller, Alan Penn, and Rui Carvalho for your valuable
>>replies. I really gain a lot from your words. As Professor Alan Penn
>>mentioned in his reply, the road system in Hong Kong is quite complicated,
>>for example, on some road, there are several traffic lines (drive ways),
>>which have the same road name, should I use one axial line to represent them
>>or is that oversimplified? Please see the attached figure, is that suitable
>>to use the highlighted axial line to represent that road?
>>
>>Many thanks in advance!
>>
>>
>>
>
>
>--
>Lucas Figueiredo
>
>Mindwalk
>http://www.mindwalk.com.br
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