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11

I found this metadata file indicating: C = County I = Interstate M = Common Name O = Other S = State recognized U = U.S.


11

IRIS is one existing open-source solution you should probably be aware of: From Wikipedia: IRIS (Intelligent Roadway Information System) is an open-source Advanced Traffic Management System (ATMS) software project developed by the Minnesota Department of Transportation. It is used by transportation agencies to monitor and manage interstate and ...


8

I had to do this just recently. Using ArcGIS 10: If you only want to symbolise the dead ends you can just set up a Topology on the roads featureclass and set the rule "Must not have dangles". this will put a marker on every feature that has a dead end. Alternatively, run the "Feature Vertices to Points" Tool (Located in Data Management Tools --> Features) ...


8

A general way of solving this problem is to find all polylines having a node whose valence = 1. A valence table may be created either in memory or on disk, using a key that is the hash of the x&y of each end point of each polyline. You may wish to truncate x and y may be truncated if polylines are not snapped. Each node is labeled by its degree (or ...


7

you can check out ET GeoTools for ArcGIS here. Beside this you can check out Feature To Line (Data Management) here but you have to some engaging in. and check out this question Find tunnel 'center line'? here... skeletisation algorithms may can help you to develop your tool. Input Dataset Result i hope it helps you...


6

I'll try to analyze your use cases from a QGIS perspective: Software that allows me to drive a specific route and store that as a working model. There is a GPS Tool for live tracking of GPS devices. But I guess you could go with the simpler version of loading the recorded GPX files into QGIS after collection. Download some GPS/County information to ...


6

This paper by Koichi Yagi shows how the accelerometer in a smart phone can be used to measure roughness. Update Whatever software you end up using, I think it needs the ability to manage road condition surveys. An important role of pavement management is prioritizing road repairs and deciding when to re-surface instead of repair. I'd like the road in ...


6

Finally i got a solution. I converted the polygon to image in arcgis using Polygon to raster tool. Then reclassified it and used Automatic vectorization. About 90 percent accuracy is obtained using this method. There are only little snapping mismatches and also the line is drawn through the exact centre. I think this is the best way if you do not have a ET ...


6

I would recommend using image segmentation with the free software SPRING, available from the Brazilian National Institute for Space Research. Documentation is available here and tutorials are available here. Image segmentation produces high classification accuracy compared to purely pixel based classification methods (e.g. ISODATA, Maximum Likelihood, etc). ...


6

Considerations First thing to consider, you might remove freeways and ramps from your road system before you start, depending on your interpretation of a block or intersection. First problem is knowing the state of your road system. If road centerlines are split at each intersection and only at intersections, then we proceed with Features Vertices to ...


5

GRASS method: v.clean in={your input vector} tool=rmdangle thresh={your threshold} out={output vector}


5

These two modeling available in ESRI software. After you can run 1st modeling we will do trim on lines model 2.


5

Collapse Dual Lines To Centerline (Cartography) This is a specific ArcGIS tool requiring ArcInfo License ArcGIS for Desktop Basic: No ArcGIS for Desktop Standard: No ArcGIS for Desktop Advanced: Yes Convert you polygons to lines first "Derives centerlines from dual-line (or double-line) features, such as road casings, based on specified width ...


5

Activate symbol layers in the advanced options of your road style.


5

You could try the Identity tool, using your line features as the input, and polygons as the identity features: "When the Input Features are lines and the Identity Features are polygons, and the Keep relationships parameter is checked (relationship set to KEEP_RELATIONSHIPS), the output line feature class will have two additional fields, LEFT_poly and ...


4

A GIS desktop and/or web solution would help you answer these question. you could use something like QGIS or GeoServer as a desktop or web solution. to get accurate county road data you could see if the county has a GIS department to obtain data. If not most States have a open clearinghouse GIS web site to download data or you could possible get data from ...


4

As with everythin in GIS there's more than one way to do it: ArcGIS has a feature to do just this, See Divide line function. Of course, remember that you rarely have an exact division unless you use the percentage option (i.e. you will get a bit left over). And, to be honest, I found it would not always work perfectly but it doesn't do too bad a job. ...


4

In ArcGIS Standard or Advanced, you can put your road network into a Feature Dataset in a Geodatabase. You can then set up a topology on the network and create a topology rule which identifies "dangles". This will identify all roads which do not connect to something at one or both ends. Note, this will also identify potential errors in your network which ...


4

There are a few ways to do this. For the intersections you can use a tool in QGIS (Arc I am sure too) called Line Intersections (Vectors - Analysis Tools). As for the blocks, what I have done for that is to have a polygon of the AOI which covers the entire area. Then I use the roads to cut that polygon into polygon segments. This will give you blocks of ...


4

I think that "node centrality" concepts, in the graph theoretic literature, may be helpful. Here is an introduction to centrality measures in graphs.


4

Update you roads direction using a formula something like if (45 <= (360 + math.atan2((!Shape.lastpoint.X! - !Shape.firstpoint.X!),(!Shape.lastpoint.Y! - !Shape.firstpoint.Y!)) * (180 / math.pi)) % 360 % 180) < 135): dir = 'W-E' else: dir = 'N-S' Then for each direction group number them in order using the first opposite ordinate to sort. ...


3

Segmented object (aka trained) classification can be used very succesfully for this problem, but I don't know GRASS enough to tell you what capabilities it has in this area. You'd get polygons though, so you'd still have to thin them or use a mean or some other transformation. You'll get even better results if you have a near-infrared band or composite ...


3

Without an Advanced level license of ArcGIS for Desktop your best alternative may be to use ArcPy and Geometry objects. Upon seeing the Comment from @Michael Miles-Stimson I looked in the ArcGIS 10.2 Online Help and found that the Polyline object has a queryPointAndDistance method which: Finds the point on the polyline nearest to the in_point and the ...


2

The obvious answer is OpenStreetMap. If quality is good enough for your purpose.


2

The Data is not quite there for what you require - but some is... The TIGER Edited Map maybe of interest to you. http://wiki.openstreetmap.org/wiki/TIGER_Edited_Map Red areas are ways which have not been edited since the TIGER import. Green areas are ways which have been edited. There still is quite a large amount of fix up required for the TIGER ...


2

ESRI has a collapse dual carriageway to centerline tool. You can get a cheap version for use with OSM. Otherwise you could select features and save as a new layer. Deleted selected from layer you used for export. Buffer feature within range of one side of the carriageway that includes the second lane. Merge shapefile with original, connect up any broken ...


2

GRASS GIS offers this through v.parallel. It can be used from QGIS with the GRASS Toolbox or, even easier, with the Sextante plugin.


2

I'm sure you're aware of the nature of Open Street Map - it's a user collected and edited resource. If you're going to use this kind of information it would be largely down to you to fix these - and in the spirit of things update the information! If you want a relatively clean network for analysis straight away, I'd suggest TIGER. ... but I think you'd ...


2

You can download files for Wales here http://download.geofabrik.de/openstreetmap/europe/great_britain/ You can download either xml or shape files. After download you can load files in program like Qgis and select appropriate layers and export them to file or database of your choice.


2

JEquihua, Try running the Intersect tool in ArcGIS with a single input (the roads) and the output type as POINT; this should give you the number of intersections. As far as the number of blocks, this is just a count of the line segments, if you need to "break" each segment at an intersection look into the Planarize lines feature on the topology toolbar. ...



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