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eddiejames_uk - all messages by user

10/2/2009 10:43:14 AM
Destination Data for NI 175 Please could someone provide me with the definition used to define supermarkets/convenience stores in the DfT 2008 NI175 destination data.

I note that this data differs somewhat from that supplied by PointX - for which there is also no definition supplied. This is becoming increasingly prominent, particularly in the validation of data sets where results are open to scrutiny by the public.

Regards,

Ed.
10/2/2009 12:26:41 PM
Destination Data for NI 175 Hi,

PointX have been unable to provide us with a definition of a supermarket or convenience store. Apparently their data is sorted subjectively by how the individual business class themselves, therefore if Alf considers his outlet a supermarket it will be listed with large superstores.

I was wondering whether the definition used in the DfT data was more explicit/quantitative i.e. based on floor area or range of goods for example?

Regards,

Ed.
10/5/2009 8:41:02 AM
Destination Data for NI 175 Hi Dan,

Many thanks for your assistance and reply. Maybe it's a question to ask Pitney Bowles as to how they've complied this dataset i.e. how they have defined supermarkets/convenience stores.

Regards,

Ed.
3/26/2010 10:37:53 AM
Destination Data for NI 175 Hi Dan,

I contacted Pitney Bowes some time ago now (email) but yet to have a response.

We had to go down the line of creating and validating our own data set for the food retail landuse as we could not rely on those provided by others without a clear definition.
Obviously the other landuses did not present a problem the definition of a GP surgery is clear cut and obvious, however the variation between a supermarket/convenience store/corner shop requires further definition.

Regards.
10/12/2010 4:12:37 PM
Speed Data Hi,

I'm currently trying to get Traffic Master ave car speeds into Accession to replace the default speeds defined by the DfT by road classification.

Traffic Master data is appended to the network bi-directionally and there represented as two links i.e. a speed for each direction. I've not worked out how to assign these speeds as per the direction in Accession.

Have any of you guys managed this?

Edward.
10/14/2010 4:07:21 PM
Speed Data Following on from my previous post RE using the Traffic Master data to replace the DfT default speeds in road based car calculations I’ve progressed my methodology as follows;

The first thing I did was calculate the weekday AM peak mean annual speeds (kph) for individual links (excluding public & school holidays) using the 08/09 Traffic Master data.

Accession does not allow bidirectional analysis so I calculated the minimum speed of each link. You could also use the average I guess.


The resultant table (link and speed fields) was imported into the Access file of the respective Accession repository.

The Access 'Road Link' table was updated using an update query on the 'CarSpeed' field.

In the above process links with no speed data are assigned a 0 value - not good if they occur on principle roads and will be treated as a road block. This is overcome by assigning an average speed to all CarSpeed fields that equal 0 - again by the means of an update query. Different speeds can also be applied to different link classifications.

The calculation was run through the road network for the car mode. NB origins residing adjacent to links with a speed of 0 will be reported as having no accessibility as they effectively snap to these and then cannot progress. It is therefore important that all links have a value, except those that cannot be driven down.

The results indicate the shortest travel time through a network for each O/D pair. NB it is important that the ITN network is used which indicates restrictions i.e. banned turns. If you import the road network as a map layer I found that this information is omitted.

I've found the results to be quite accurate and much better than using the default speeds by link classification provided by the DfT.

Let me know if you have any further questions, and let’s hope that future editions of Accession are able to consider bidirectional speeds and provide the facility for displaying the route/s taken.
It would also be useful if Accession would consider O/D pairs rather than routing to the nearest destination. Any thoughts?

Ed.
11/29/2013 3:42:48 PM
Running out of memory Hi Ian,
I'm having the same problems regards memory when using the ITN network in calculations (32bit machine). Using the ITN network for the county (Derbyshire) throws up the error message you describe, even with just one OD pair.
Did you upgrade to 64bit and has this solved the problem or are you continuing to operate making do without the buffer? If so what were the associated costs with the upgrade?
Unfortunately the option of cropping the network to the boundary in Derbyshire is not an option as the residual network is still quite large.

Regards,

Ed.
12/2/2013 3:45:11 PM
TRACC Suggestions TRACC Suggestions

Estimated Calculation Times
A percentage progress bar is provided, however there is no indication of projected calculation/import time. Providing this information as a summary beforehand would allow the user to review and consider whether or not to proceed and also indicate when to return to the computer once finished.

PT Network Export
I currently use Accession software as a means of translating the unusable ATCO CIF public transport network file into a workable MS Access file.
Would it be possible to provide a button in TRACC that coverts the data in a similar way so it can be exported as an Access file? Alternatively, is anyone aware how the file could be converted other than using Accession?
edited by eddiejames_uk on 12/2/2013
5/1/2014 10:55:14 AM
Data availability Excellent, many thanks Keith. Will you be updating the rail CIF for 2014?
11/26/2015 9:58:45 AM
Destination Data for NI 175 Hi All,



Can anybody advise from where I can source the latest destination data? I'm particularly interested in the food stores i.e. supermarkets and convenience stores. I require this data for the County (Derbyshire) and appropriate buffer.




Regards.




Ed.
11/30/2015 10:03:46 AM
Destination Data for NI 175 Hi Rowley,
How did you create the destination files? Did you query the OS address database or similar? I've managed to find the following which appears to provide a comprehensive list of all 'major' supermarkets in the UK which is maintained and available for use. http://geolytix.co.uk/blog/category/open-data/supermarket-locations/ Unfortunately it doesn't include the smaller or independent stores that I'd probably also need to include, but it does provide a useful base.

Additionally, do you know where to source a comprehensive list of PO's? The PO website doesn't appear to provide this - you can only query your nearest branch/es.

Thanks.

Ed.
12/3/2015 4:40:17 PM
TRACC Road Network Hi,
I'm running a calculation at present, however I can't prevent the journey routeing onto the motorway which passes overhead i.e. not a junction. Obviously in reality this route cannot be utilised.

I've tried several road networks, importing the ITN through the respective tab and also as a shape file. I've also tried the OS Highways layer which also gives the same results, despite the links not actually intersecting like the ITN does.

What am I missing here? Any help appreciated.

Ed.
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