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6

The following is a rough outline of what you might do. I won't include a great deal of detail, you can research further using these terms and/or ask new more specific questions. Note: you will need to careful of coordinate systems. Firstly that they are the same for your datasets, and second that they use metric (metres) horizontal units (not actually ...


6

Yesterday I had no time to create it in details... See my solution in 4 steps: CREATE OR REPLACE VIEW bd_segment AS SELECT ST_PointN(geom, generate_series(1, ST_NPoints(geom)-1)) AS sp, ST_PointN(geom, generate_series(2, ST_NPoints(geom) )) AS ep FROM -- extract the individual linestrings (SELECT ...


5

The only geoprocessing tools you need for that is Intersect (Analysis toolbox) and Join Field (Data Management toolbox). Run Intersect on the land use and watershed polygons which will result in the intersection of those two layers (your watershed layer will be clipped to the borders of your land use layer while having all the attributes preserved). Then ...


5

Very interesting question! Found a couple more examples and included a brief quote and their citation (quite fun to see how GIS software can be used in completely nongeographical applications): LASER CONFOCAL MICROSCOPY AND GEOGRAPHIC INFORMATION SYSTEMS IN THE STUDY OF DENTAL MORPHOLOGY "...original specimens of Recent teeth can often be optically ...


4

There are other applications in processing microscope images like the one from your example. A well known geospatial image processing software called eCognition was developed originally by Definiens - a company who does a lot of image processing in the medical and life science domain. See this older press release: ...


4

I would use Python's itertools and a SearchCursor for a very efficient way to find the spatial relationships you are after. You can incorporate the geometry methods overlaps, contains, and equal to get at the geometry properties. Start off by creating a function to better organize the workflow and for repeatability def findOverlaps(x): Open a search ...


4

It's important to note the job titles associated with positions that supersede GIS Technician or GIS Analyst. You won't (hopefully) find too many job postings looking to hire for a GIS Analyst position with the requirement of 10 years of experience. After 5-8 years as a GIS Analyst you would likely start looking to transition to a GIS Coordinator/GIS ...


4

GIS is still a relatively new technology, despite its exploding popularity and application potential, and so it will take time for HR to understand exactly what GIS is for, what a GIS "Analyst" does, and what they should be paid. However, if they see data from reputable national organizations that indicate higher pay is typical (and they will therefore ...


3

Assuming you have an older version of GDAL/OGR, you can use OGR SQL to cast the geom field to a geometry. For example: ogr2ogr -f "ESRI Shapefile" "sample.shp" "geo.csv" -sql "SELECT *, CAST(geom as geometry) FROM geo" This will create a new shapefile using the WKT data as the geometry. You can use the same query with ogrinfo as well: ogrinfo -ro -sql ...


3

Many thanks, I am interested in the topic for a long time but I only knew a few applications in: Biological morphometric analysis in APPLICATION OF SPATIAL STATISTICS TO LATENT PRINT IDENTIFICATIONS: TOWARDS IMPROVED FORENSIC SCIENCE METHODOLOGIES with ArcGIS or A GEOMETRIC MORPHOMETRIC APPROACH TO FINGERPRINT ANALYSIS, ... Archeology Computational ...


3

In order to get at the classes you describe, you will need to incorporate a sophisticated classification algorithm and ancillary data derived from the imagery. I would recommend two approaches: 1) an object-oriented image segmentation (IS) approach using IS software such as eCognition or 2) a pixel-based non-metric, decision tree (Random Forest) approach ...


3

Calculate the intersection (i.e. overlap) between the two layers (Vector > Geoprogressing Tools > Intersect...). Use the drop down menus to select the two layers, and specify a location to save the output shapefile. The resulting layer will have attributes from both input layers (e.g. "actual cover" and "target cover"). You can then filter this layer ...


2

in QGIS, Topology Checker plugin can propably solve your problem


2

I have an idea what may work for you. It is going to be based off some assumptions, but it would help narrow down your list of possible identical features. This would not be an automated process, but it would require manually looking at the duplicates. Based off the comments, it seems like the automated tools don't compare attributes so this would help ...


2

Here's an idea, based on using Feature To Line. With ESRI, the tool is only available at the ArcInfo/Advanced license level, but with QGIS I'm sure you can find an version of it. So you could, as I often do, supplement your ArcView/Basic license workflow with free QGIS tools. Run Feature To Line to convert the lake features to lines (make sure you're ...


2

This is imo a great question. If you would be interested in just finding the intersection between two polygons, you'd use the Intersect GP tool and then adding the area of the resultant features back to the wetlands. But you are interested not in intersection yet essentially in the edge, or a segment which polygons share. There is a very nice GP tool in ...


1

Here is a great video that helped me out for explaining Cost-Path: https://www.youtube.com/watch?v=d0Eywj4pIu8 As mentioned before, this requires a DEM to create a slope raster using Spatial Analyst Tools -> Surface -> Slope. However, for what you are looking for (get a detailed perspective on hiking from point A to point B), you can implement Tobler's ...


1

In your case, the best tool is probably the "Path Distance" Tool, which will take your DEM into account to adjust the speed. There is a long description on this page on the option to set the speed. Note that the relationship between speed and slope depends on your travel type. By bike, you go faster downhill than uphill, so this is more like a linear cost. ...


1

Step 3 of your list is definitely wrong in most cases. It spoils your data, because it does not change the coordinates itself, only the CRS. Instead, you have to save the data from the untouched CRS to another filename and CRS. For the Google background of the Openlayers plugin, project CRS and the CRS of the Google layer must be EPSG:3857. Other layers ...


1

This will not solve all your issues, but its a good start. This script in python 2 works with a csv file with three fields: id, latitude, longitude. You can also add time field and implement the codes for calculate the average speed. It calculates absolute distance walked(diference between last and first point), also calculates the sum of distance to all ...


1

I see this more as a statistical question than a GIS one. Or maybe it's just my training. Assuming there is data representing each tree (labelled something like Tree1, Tree2, etc. in the database) and there are also fields for each of the states (survived, born, died) in each layer. I would write up a research question for each, something like this: What is ...


1

You need to create a spatial join. The MMQGIS plugin does this quite easily - MMQGIS -> Combine -> Spatial Join. A tutorial is available here.


1

The Topology Checker plugin is a good tool if used correctly. You still have to have a fundamental understanding of your data AND you have to make the 'corrections' manually. The plugin will highlight what it thinks are errors. It is up to you to then examine each and make the appropriate decision for you and your data. With 90 000 items in your layer, you ...


1

You can do this in SQL using a spatial self join. You don't state which SQL dialect you are using, so this example uses Postgres/Postgis, but it could be easily adapted to Oracle or SQL Server. Assuming a table called buildings, with geometry stored in a column called geom: SELECT a.id, b.id from buildings a, buildings b WHERE ST_INTERSECTS(a.geom, ...


1

Python is all about combining many operations into one. In the script below, I iterate through feature classes in a workspace. For each, I iterate through a list of other feature classes to perform a near analysis on. I perform the near analysis, and with a little help of a dictionary as well as field calculate, I transfer the results into new fields. ...


1

Here is an excellent source of ports related information: http://www.portsdb.com Currently they provide access to the data via REST API, but I think you may ask about the database dump. There is free and paid option. For basic port information free one is good enough to start.



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