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29

I think the stock/obvious answer would be to use a spatial database (PostGIS, Oracle, SDE, MSSQL Spatial, etc) in conjunction with a metadata server such as esri's GeoPortal or the open source GeoNetwork application, and overall I think this is generally the best solution. However, you'll likely always have a need for project-based snapshots / branches / ...


26

I played with this topic a lot some time ago. You can find some examples here: Dobrou extensions plugin examples Dobrou extensions plugin homepage Using Sporttracks and this plugin, gps tracks can be converted to KML and displayed in Google Earth. It supports some ideas mentioned here - track coloring based on color gradient, direction arrows and much more. ...


22

I've always done it as width. For example you create a buffer around each point that represents speed and then dissolve the buffers into one. Narrow areas indicate bottlenecks. For an example see: http://www.fmepedia.com/index.php/Bufferer Of course, you can even color code the buffers before merging them. For an example see: ...


21

Good question. Geography, and later GISc have been struggling to incorporate 4th dimension since Torsten H├Ągerstrand brought time into geographic research. Couple of things from the top of my head: One of the solutions is to use 'space time aquarium' where in 3D space you can use X and Y to represent location in space and Y to represent time. Two names ...


19

A simple and efficient way is to color the segments depending on their speed. For example, "fast" segments can be displayed in green and "slow" segments in red (other colors can be chosen of course). Example on an orienteering-running GPS trace using the software Chmuk: Another example with the software quickroute: The parts of the route where the ...


15

This is a wicked problem. We've tried various systems, which have all worked to varying degree for a time, and eventually grown unwieldly and started to fall apart as more and edge cases which don't quite fit are encountered. That said, each of the systems we've used is way better than nothing, proving the maxim that any system is better than no system. ...


14

Metadata is by far the most important issue here. If metadata answers whom, when, why, where it's an acceptable metadata record. Having work experience in large companies with just a few GIS users (around 30) we had major issues to control data, specially versions and permissions. One side of this can be solved with extensive documenting of data (metadata) ...


13

I think the literal answer to your question is "not really" (aside from things like blue=water or blue/red=Dem/Rep). It depends on how/what other data is displayed on a map and the map's purpose whether, for example, county boundaries are a light color or dark color. There are plenty of places where color choice is discussed. Some examples of books (I'm ...


12

I think you may be interested in work described as time geography, and you may want to use search terms such as space-time-path or space-time-cube. In the space-time-cube technique I would imagine you could still use color to represent velocity of the movements, although it is inherently represented in the space/time distance between nodes on your path. ...


10

You can record the position of the vehicle with a regular time interval and gradually fade out old time points. Adding a line at each point whose length is representative of the speed can help too. Below is an example from Microsoft Research. It's quite easy to see the relative speed of different countries in this graph. ...


10

Since you have multiple objects being tracked I would go with using color to differentiate objects and instead of colour to show speed, I'd use thin lines perpendicular to the direction of movement illustrating 10 second intervals (say). Closer lines = slower. Not the best sketch below, but you get the idea:


8

You might be interested in my slides from a SXSW panel on geotemporal visualization. While they don't cover every single approach, they do a pretty good job of offering examples for the most common approaches (note that many of these examples require a browser with SVG or Canvas support, so not IE<9): Showing time as a line on a map Showing time as map ...


8

How about arrow symbols? Length of arrow = speed of the object at that location. You also get direction for free. And the whole thing is very intuitive -- no need to glance over at the legend to remind yourself of the interpretation. It's used all the time for wind-speed maps, but there's nothing saying you can't symbolize objects this way too: ...


8

I think I would go for something in the direction of Trevesys suggestion but only with dots instead. Longer between the dots means faster and closer between them means slower. It is easy to think of the speed like, high speed should get a more powerful visualization, but I am tempted to think the reverse because the symbol is bounded to a special place on ...


7

We have used a file system organized hierarchically by: - geographic extent (country or continent) - data provider, licensor - domain/dataset - date/version After that we have a policy to separate the source data (in the same format that was on whatever CD/DVD that we got from the provider) from any derived datasets that we produced within our company. The ...


7

You might want to have a look at some of Gennady & Natalia Andrienko's papers. They have published extensively on the issue of geovisualization of movement data and some of their output might be helpful here. Cooper Smith has also done some interesting work using processing.


7

If you're looking for a video output, commercial tools like EONfusion can make nice 3D environments with temporal information. Similarly, I agree Google Earth (and its plugin) are a simple tool for visualizing interactive temporal data. Visual Complexity keeps a database of network visualizations, many of these are spatio-temporal visualizations, such as the ...


7

I don't have an answer for everything, but will give this a shot...I work for a utility setting up a GIS system for land acquisition, maintenance and engineering. We have a whole system of checks and balances where the behind-the-scenes IT server information is not something that I maintain, but can give you a glimpse of what we've seen with our production ...


6

That is actually something you will find little documentation on publicly. There are classes/workshops that ESRI charges for or that you can attend at the ESRIUC but less in the public space. A couple of the points you mention come out of good DBA practices; but some really dont and really depend on your sytems and needs. For integrity, for sure a stable ...


5

According to Corine Land Cover Legend, "industrial" is purple. This convention relies solely on solid colors, no hatchings or similar.


5

This is relative; best colours for associative data. I say this because, when I was doing geography in high school, it was quite the taboo to draw anything other than water on the map as blue. Often losing marks when we did, even getting close to purple was avoided. When I went to college, major highways were colored blue, in fact, a trademark blue; Nova ...


5

I recently came across some of the work of Sidonie Christophe that has particular bearing to this subject. While in the particular paper I'm referencing (Christophe, 2011) she proposes a more general set of cartographic rules governing the choice of color for objects, the rules she proposes are so intuitive that I suspect they are in general implemented in ...


4

I really like using Google Earth for temporal data. Really nice platform for communicating, very smooth animation and relatively easy to 'program' Google Earth & Time Should be a list of animated chloropleths and volumetric there... have fun!


4

I've stumbled over the following site http://www.planning.org/lbcs/standards/ (Land Based Classification Standards) Theres a PDF and a spreadsheet that define certain colours to certain types, But I agree with everyone here in saying it really depends on what your showing.


4

If your data is in a database then ideally you'd use a NULL value: a representation of "missing information and inapplicable information" However this could cause issues with client applications and code, and I don't believed NULL is supported in DBFs. What that value should be I guess is different for different organisational conventions. Whatever ...


4

Most rasters I've come across use -9999.0 for floating point data as a convention, and GDAL will use -dbl_inf when you're writing code for an image that doesn't have a nodata/dummy value. 8-bit RGB will usually use 0 0 0 or 255 255 255, or have an alpha or mask channel. GML 3 coverages (for which there isn't a great deal of support at the moment, but that ...


4

Current replies all give good advice. A general rule (from the scientific computing community) that works well in cases where you cannot store true nulls or NaNs is use the smallest (most negative) value the field will (validly) hold. Examples: A 7.2 decimal field can hold a value as small as -9999.99. An integer raster can hold numbers as small as ...


4

I like very much to talk about ArcObjects and that kind of discussion, but people may not find it suitable here. Well I always have a project for specific, ArcObjects code only. That means I can reuse these methods and classes anywhere else. (sounds like your Common). This is how I do it: Solution Business Project Models (this is how I name the ...


4

I would suggest to use multiple map services to take advantage between dynamic vs cached (tiled) services. For basemap data that does not change often you should use cached services (this will improve performance).



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