On Thu, 31 May 2007 17:47:55 +0100, Alain Chiaradia
<[log in to unmask]> wrote:
>Alan
>
>In London GLA the network is about 13,000km in length
>
>Transport for London Strategic Network TLRN is a network of 580km of
London's red roads about 4.5% of the network, which carry 35 per cent of
the London's traffic (Source Tfl).
>
>Strategic Road Network SRN 520 km SRN about 4% of the network
>
>Network of Interest NOI c2000km 15% of the network
>
>Altogether they carry most of the traffic.
Thanks alain, this is very useful information.
Pitty no one knows what a street is...
All the best,
Rui
>
>Every weekday there are:
>- 11 million car or motorcycle journeys
>- 6.7 million bus journeys
>- 5.5 million journeys on foot
>- 3.6 million tube journeys
>- 1.8 million rail journeys
>- 0.35 million bicycle journeys
>________________________________________
>
>Alain Chiaradia GradDipl (AA) Arch dplg
>Director
>
>SPACE SYNTAX
>________________________________________
>
>
>-----Original Message-----
>From: Alan Penn
>Sent: 31 May 2007 08:59
>To: [log in to unmask]
>Subject: Re: A topological pattern of urban street networks
>
>Bin,
>
>The Pareto 80/20 rule is nice, but isn't it really just a rule of thumb?
>
>On the second point - your student's work comparing axial named street and
>'stroke' sounds interesting. Is it available to be seen anywhere?
>
>On the principle of 'well defined' I have a question. How might your
>definitions be applied to design of a new city?
>
>Alan
>
>> >
>> >> One of the problems I had in the Physica A paper was that we do not
>> know
>> >> what a street is. There are several representations out there, but
>> there
>> >> is no uniquely accepted concept?
>> >>
>> >
>> > Agreed - an argument for a (comparatively) well defined concept like
the
>> > axial line perhaps? :-)
>> >
>> Well, I cannot agree with the point. Through the experiments, we see the
>> concept of streets based on perceptual grouping is pretty clearly
>> defined, much better than axial lines. People may argue that the
>> criteria of good continuity is a bit vague. In fact, we tried different
>> threshold angles (actually a series from 20 to 90 degrees) for merging
>> (or grouping) street segments to form individual streets, and found no
>> big change in the illustrated pattern. One of my students Chengke Liu
>> has testified three models: axial, stroke, named streets, and found the
>> latter two are the best.
>>
>> Cheers.
>>
>> Bin
>>
>> --
>> ------------------------------------------------
>> Bin Jiang
>> Department of Land Surveying and Geo-informatics
>> The Hong Kong Polytechnic University
>> Hung Hom, Kowloon, Hong Kong.
>> Tel: (852) 2766 4335, Fax: (852) 2330 2994
>> Email: [log in to unmask]
>> ------------------------------------------------
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