<div>Hi Max,</div><div><br></div>Yes, we thought about it already and it's on the GSoC ideas list of 2010.<div>We even had a student in 2010 from Karlsruhe University, who picked that topic, but then left GSoC very early unfortunately due to lack of time.</div>
<div>Other years candidates who picked that topic were not selected, because their proposals were not good enough.</div><div><br></div><div>I thought the "contraction hierarchies" algorithm does a lot of pre-processing. That's why it's fast.</div>
<div>Do you think this pre-processing is suitable for pgRouting and doesn't constrain it's flexibility to select data by attributes, geometries, etc.?</div><div><br></div><div>But if we have a GSoC candidate with a strong and feasible proposal for "contraction hierarchies" (and at least two mentors, who will support), such a candidate's proposal would be probably ranked high.</div>
<div><br></div><div>Daniel</div><div><br></div><div><br><div class="gmail_quote">On Fri, Feb 24, 2012 at 8:57 AM, Max Weninger <span dir="ltr"><<a href="mailto:max.weninger@gmail.com">max.weninger@gmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Hi<br>
<br>
Has the "pgrouting team" ever thought about implementing<br>
a routing solution based on "contraction hierarchies"<br>
<br>
Details about the concepts can be found here<br>
<a href="http://algo2.iti.kit.edu/routeplanning.php" target="_blank">http://algo2.iti.kit.edu/routeplanning.php</a><br>
<a href="http://code.google.com/p/monav/wiki/ContractionHierarchies" target="_blank">http://code.google.com/p/monav/wiki/ContractionHierarchies</a><br>
<br>
Example implementaions e.g. here<br>
<a href="http://project-osrm.org/" target="_blank">http://project-osrm.org/</a><br>
<a href="http://code.google.com/p/monav/" target="_blank">http://code.google.com/p/monav/</a><br>
<br>
Routing with such engines is extremely fast (milisecs)<br>
even for really large networks<br>
<br>
Regards<br>
<span class="HOEnZb"><font color="#888888"><br>
max<br>
</font></span><div class="HOEnZb"><div class="h5"><br>
On Thu, 16 Feb 2012 14:52:46 +0900<br>
Venkatesh Raghavan <<a href="mailto:raghavan@media.osaka-cu.ac.jp">raghavan@media.osaka-cu.ac.jp</a>> wrote:<br>
<br>
> Dear All,<br>
><br>
> As most of you must be aware, the<br>
><br>
> Google Summer of Code 2012 has been announced [1,2]<br>
><br>
> Some ideas that comes to my mind are<br>
><br>
> 1) Implementing of map-matching algorithms as of the pgRouting<br>
> function. Python code for the algorithms that we implemented in 2010<br>
> (See <a href="http://cs-test.ias.ac.in/cs/Downloads/article_45523.pdf" target="_blank">http://cs-test.ias.ac.in/cs/Downloads/article_45523.pdf</a>) could be<br>
> made available and the main work would be to integrate/improve<br>
> them for implementation as pgRouting and/or SORouting (see item 2<br>
> below)<br>
><br>
> 2) Implementing routing as a service. a) Use Web Feature Service<br>
> (WFS) as input b) implement routing functions as Web Processing<br>
> Service (WPS) c) Publish<br>
> routing result as WFS. That would be SORouting (Service Oriented<br>
> Routing instead<br>
> of pgRouting. Since I am also a ZOO-Project (<a href="http://www.zoo-project.org" target="_blank">www.zoo-project.org</a>) PSC<br>
> member which is a OGC compliant open-source WPS implementation, I<br>
> would take this opportunity to promote the use of ZOO for<br>
> implementing SORouting.<br>
><br>
> 3) Route selection based on multi-criteria decision model to enable<br>
> alternative<br>
> route selection based on conditions at the destination. For example,<br>
> route to<br>
> the nearest hospital depending not only upon road conditions but also<br>
> conditions at several destination hospitals (bed availability,<br>
> availability of<br>
> medicare specialists, availability of ICU etc). The condition of<br>
> destination could be implemented using the OGC SOS standard.<br>
> Regarding multi-criteria decision using AHP (analytical hierarchy<br>
> process). There are several literature available [3],[4]. My student<br>
> Sittichai (who writes<br>
> on the pgRouting users list) has already started some work and could<br>
> perhaps take up the work if he finds a mentor.<br>
><br>
> Best<br>
> Venka<br>
><br>
> P.S. Also Cc to ZOO-PSC since there may be some mentors there to help<br>
> with the WPS implementation for SORouting<br>
> ------<br>
> Prof. Venkatesh Raghavan<br>
> Osaka City University<br>
> Japan<br>
><br>
> [1]<a href="http://www.google-melange.com/gsoc/homepage/google/gsoc2012" target="_blank">http://www.google-melange.com/gsoc/homepage/google/gsoc2012</a><br>
> [2]<br>
> <a href="http://google-opensource.blogspot.com/2012/02/google-summer-of-code-2012-is-on.html" target="_blank">http://google-opensource.blogspot.com/2012/02/google-summer-of-code-2012-is-on.html</a><br>
> [3] <a href="http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=5567840" target="_blank">http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=5567840</a><br>
> [4]<br>
> <a href="http://www.tandfonline.com/doi/abs/10.1080/13658810601135692#preview" target="_blank">http://www.tandfonline.com/doi/abs/10.1080/13658810601135692#preview</a><br>
><br>
><br>
> _______________________________________________<br>
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</div></div></blockquote></div><br><br clear="all"><div><br></div>-- <br><span style="font-family:arial,sans-serif;font-size:13px;border-collapse:collapse">Georepublic UG & Georepublic Japan<br>eMail: <a href="mailto:daniel.kastl@georepublic.de" style="color:rgb(66,99,171)" target="_blank">daniel.kastl@georepublic.de</a><br>
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