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6

The +1 is a convention. It's all about converting the ranks to percentiles. Consider 99 iterations. The rank will run from 1 through 99 (in whole steps). You can convert the rank to a percentile by dividing by 99 and multiplying by 100. That would produce percentiles from 100/99 = 1.01% to 99*100/99 = 100%. That lacks a desirable symmetry: you're ...


5

Check i2maps framework. There are two examples using animated data that might be of some help: Agent-based simulation: A micro-simulation of pedestrian flows on the campus. In this example we do not use a server-side simulation engine but test browser's performance to process and visualize dynamic OpenLayers objects. Public transportation: A ...


4

I would recommend either Qrule or SIMMAP. The suitability of a given model is dependent on what type of neutral landscape structure you wish to simulate (e.g., edge fractal dimension, mean patch size, juxtaposition, etc...). Qrule: http://www.umces.edu/al/program/gardner/qrule SIMMAP: http://www2.montes.upm.es/personales/saura/software.html


3

No need for expensive proprietary solutions, this is called the Traveling Sales Person (TSP) problem and luckily for you this PostGIS extension PG Routing already has this cracked. Better yet it's free and opensource! Just vanilla web app stuff to write some back end code to that you can run those queries over HTTP. Happy mapping!


3

I am not sure what tools you are looking for (not sure what do you want to simulate) but there are few programs that deal with landscape indices: Fragstats - http://www.umass.edu/landeco/research/fragstats/fragstats.html Patch Analyst - ArcGIS add-on (link to presentation - http://www.cnr.uidaho.edu/rsgis/docs/Fragmentaiton.pdf) GRASS GIS have a module ...


3

In ArcGIS 10 you can enable time on a layer (with the proper time fields) in the Time tab of the layer properties. Then using the Animation toolbar you can save to an animation file. See the help links for more details: http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#/About_enabling_time_on_data/005z0000000p000000/ ...


3

It seems what you want to implement is some sort of agent-based simulation. This might be an overcomplicated thing to do if all you want is some mock data for testing your real-time map app. I'd recommend to get hold of real ship gps tracking data and use that to update your database. The data provided by the AIS system might be good for that. For example, ...


2

Don't know if this helps you, because I think UTDF is not very "europe related". What I know, there are a lot of different combinations of spatial database model <-> Exchange Format <-> Traffic analysis software. It depends mostly on the exchange format which is supported by your traffic analysis software, but its very hard to get out of the box ...


2

A contour map is rarely a good starting point, especially if you already have a (gridded) elevation model. Contours are cartographic, rather than topographic, features. Having said that, if the DEM was derived from a contour map to begin with, then maybe you should return to the source.


1

Maybe there's someone on the web who has ArcGIS Server for Network Analyst and has published a closest facilities layer, similar to this sample service. You could adapt this javascript code, to perform the task. Often these sorts of analyses use choice models that take the "n nearest facilities" as an input, such as multinomial logit models. For example ...


1

You can use our RW Net 4 library, either calling it from .NET or use Python as a scripting language. Prices start from €1000 for a solution covering the needs you specify. You will need a street network covering your area of interest, for some areas good and free sources exist.


1

you might want to utilize the Solver extension in excel, I have used it a few times in liner programming. here is a link on a crash course on LP, utilizing Solver: http://www.economicsnetwork.ac.uk/cheer/ch9_3/ch9_3p07.htm


1

Your question is poorly stated. It as at once general, as it asks if anyone has ideas about how to implement MFDs, and specific, as it seems to ask what is wrong with you code. I'll try to answer this second conceptualization of your question here. You claim that the code you've posted is not optimized. I have rewritten the code below as I think you should ...



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