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18

The INSPIRE data specifications define some standard styles for portrayal of topographic data (transport network, hydrography, administrative units, etc.). See for example the section "11.Portrayal" of this document for hydrography. If you are looking for standards for the representation of style, see SLD and GSS.


16

If you use that id for something like as a foreign key in relation to another table your whole database will get in big trouble if you have to move a point for some reason. Probably you then will have to keep the id even if it not describes the xy-coordinates any more. As a unique key is often the best to have something not telling anything about the data, ...


11

The closest I've found to an answer is in the DMA technical manual 8358.1, which states: 3-2.2.1 For that portion of the world where the UTM grid is specified (80° south to 84° north), the UTM grid zone number is the first element of a Military Grid reference. This number sets the zone longitude limits. Zone 32 has been widened to 9° (at the ...


8

This convention is just begging to bring out bugs from bad command interpreters. (It is all too easy to confuse initial digits with a number.) Your software's success today in avoiding such bugs is no guarantee that they won't appear in future releases. This has happened multiple times, over decades, with ESRI's GIS software. This behavior has been ...


8

Well known text for geometry is defined in OGC 01-103r4 (amongst other places). Section 7 of that document provides the syntax. There is also a list of SQL functions relating to those in Part 2 of the Simple Features spec (also an OGC product). The ISO documents are just a more expensive way to get much the same thing. There are useful extensions such as ...


7

I recently noticed this project by the GeoVista group that is attempting to standardize map symbology for critical incidents (sponsored by the Department of Homeland Security). They have a few conference papers that should be helpful for standardized emergency symbols. Note this also is not an international standard, but I would check out the references for ...


7

Desktop GIS Opensource: udig, QGIS (Releases currently only supports WFS, developer version contains experimental WFS-T support check the QGIS bug tracker.) Commercial: Mapinfo Professional Web GIS Opensource: OpenLayers, Mapbuilder & Mapbender Commercial: Internet Mapping Framework (IMF) Most information taken from geoserver.org.


6

Avoid Numbers if you can - Earth Sciences has a good example http://library.oceanteacher.org/OTMediawiki/index.php/General_File-Naming_Convention_for_Earth_Science_Datasets#Filename_Sections_in_the_Order_They_Should_Appear Spaces can trip you up to - some old DOS based commands for moving files break if space are involved - use "_" (underscores) is a wise ...


6

I emailed USGS and got this response: Greetings Jaime: zone 32 is 9 degrees wide in zone designator V is 9 degrees wide for the purpose of including the west coast of Norway within a single zone. Zones 33 and 35 are 12 degrees wide in zone designator X for the purpose of putting Svalbard into two zones instead of three. In both examples, the UTM ...


4

Adding on from Nicklas answer and my comment. I would say the most used convention and most recommended is just to use a auto-incrementing ID, eg start at 1 and just keep going. No logic and simple. If you have a distributed system, or don't like auto-incrementing numbers, you could use a GUID. Most databases will handle creating this kind of ID for you. ...


4

Follow up question: Is it best to create and maintain the unique id in the DBMS (SQL Server) or in the GIS software (ArcGIS)? I'd strongly suggest checking for uniqueness inside the DBMS. That's one of the many strengths of DBMSs. It also allows you to access your data with different GIS software that probably wouldn't be aware of the unique ...


4

On a comical stance... http://www.cartotalk.com/lofiversion/index.php?t2542.html 'emergency symbol library' links to the map.. Homeland Security Mapping Standard - Point Symbology for Emergency Management http://www.fgdc.gov/HSWG/index.html Tip: Try an guess the symbols


4

It's been a year and nobody will care, but just in case someone arrives here... Actually Ian's answer is incorrect. WGS84 approximates Earth by an elipsoid, which is basically a deformed sphere. EGM96 is a more complex model based on the gravitational force of the Earth (which is not constant) that defines what "sea level" or "up/down" mean, a smooth but ...


4

Depending on your level of accuracy I would suggest the following: Low level Accuracy Use QGIS for Android (free and has a gps toolbar) along with your tablet or handheld native gps High Level Accuracy Use QGIS for Android along with your vendor gps


3

That whole section of the website is available for local download on their GEOSCAN site, as of today (April 3, 2012). I enquired with NRCan in Feb or March, and just got a reply email from CTI with said link. Hurrah! Really made my day.


3

These might be some good contact/reference points. Opensource routing, It looks as though they spun their own. Very cool with walking and biking routing as well as driving! Opensource geocoding reviewed - This from March 2010.


3

The referenced paper is overly fussy, IMHO, because there are some preliminary questions to address. Chief among these is that the NSSDA implicitly models errors as approximately normally distributed and independent. Both of these assumptions are questionable, especially the second, and ought to be checked first. Their effects will be much stronger than ...


3

Any "Open" or "Select" file dialog is going to do sorting assuming the files are named using letters. So if you are using an eight (!) digit unique number for every project file sorting will quickly become illogical. E.g. 1 10 2 20 3 etc. Besides there'll be plenty of GIS tools that will still be assuming files that conform to the MS DOS 8.3 filename ...


3

For French readers, Marc Leobet wrote and published a nice introduction to INSPIRE (Second edition). See associated post.


3

Our identification scheme was not chosen by me but is as follows: 2,3,4 character code which is the class of asset and a 6-digit sequential number (you would choose whatever digit count works for you). A stored procedure creates these IDs and relies on a couple of non-geodatabase tables in the same SQL Server database. I do keep a separate, sequential ...


3

I had no idea it moved either! http://en.wikipedia.org/wiki/Arctic_Circle The position of the Arctic Circle is not fixed, but directly depends on the Earth's axial tilt, which fluctuates within a margin of 2° over a 40,000 year period,[2] notably due to tidal forces resulting from the orbit of the Moon. The Arctic Circle is currently ...


3

I am not aware of any standards, look at the difference that exists between Google, Bing, Yahoo, DeLorme...etc. I have two suggestions for you: If you have access the ESRI Data & Maps media, there are layer files for the ESRI style street maps. If you like their appearance, it shouldn't be too hard to hack at those layer files to make them fit your ...


3

In the ESRI world, WFS-T is supported starting with version 9.3 in ArcGIS Desktop for visualization of WFS only and ArcGIS Server for publishing and edition through a WFS-T client.


3

I am using ST_relate_summary function, acting as the requested ST_Relate_readable(), that I posted into code.google as simple a SQL/PostGIS code. It is not from a standard library, neither a systematically tested or optimized one. Thanks to Mike about JTS Topology Suite: JTS offers a (very good!) graphical interface, reporting spatial predicates... I need ...


3

This following one is correct: /WFS_Capabilities/Service as defined by the following portion of the schema definition for version 1.0.0 <xsd:element name="Service" type="wfs:ServiceType"/> Take a look at 12.3.3 Service section in the Web Feature Service Implementation Specification (OGC 02-058)


3

As the programmatic lead for the SDSFIE standard, I recommend that you go to sdsfie.org and learn more about the standard. You can directly ingest the ESRI GDB version of SDSFIE 3.0 into CJMTK. By the way, SDSFIE is also a DoD mandate (for use on installations & environment missions as well as Civil Works) and it is registered in the DISR. We are ...


2

I found an article[1] about the history of grids and datums in Norway. I do not understand many of the details in the article, but it seems like 32V was extended for compatibility with previous grids. The article does not offer a clear explanation about Svalbard. [1]: Mugnier, C. I. Grids and Datums: The Kingdom of Norway. Photogrammetric Engineering and ...



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