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11

Actually it's not all that situation dependent and is all about statistical error. Any time you resample to a higher resolution, you are introducing false accuracy. Consider a set of data measured in feet at whole numbers only. Any given point may be +/- 0.5 feet from its actual location. If you resample to the nearest tenth, you are now saying any given ...


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 ...


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 ...


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 ...


4

there are a few examples of animal counting by remote sensing (whales, gnu, crocodiles, seals...), but they used higher resolution satellite images (<1m) or aerial photographs (see this paper) and there was a clear spectral difference with the background (sometimes in UV or infra-red)). As a rule of thumb, you should have around 10 pixels to detect an ...


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

ArcGIS has a few tools in the Spatial Statistics toolbox that might be useful. Mean Center Identifies the geographic center (or the center of concentration) for a set of features. Median Center Identifies the location that minimizes overall Euclidean distance to the features in a dataset. Central Feature Identifies the most centrally ...


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

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 ...


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 ...


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

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: ...


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 ...


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 ...


1

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 ...


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

in QGIS, Topology Checker plugin can propably solve your problem


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

Frequency and summary statistics were definitely present in version 9.2, frequency has been around since I've been using ESRI products (early 1990's). Summary Statistics offers more powerful statistic types over frequency, and can work with a basic license (ArcView) where frequency needs advanced (INFO) license. Same with Intersect, Identity and Union, ...


1

To aggregate the clusters use grouping which produces a field SS_GROUP then for each unique SS_GROUP in the feature class create a convex hull then use Feature to Point to obtain the centroid of that particular cluster, with polygons you can specify inside to guarantee that banana shaped polygons produce a centriod that is inside the polygon but that wont ...


1

One fast way for doing visual analysis is to use DEM as starting point and classify it with pseudocolors. You can edit the class ranges and colors etc. to suit your needs. For further analysis you can use the raster calculator. The next screen capture shows how to make a black/white image where pixels with height<10 m are white and pixels above 10 m ...


1

In my experience, satellite imagery, even high resolution, has not been too effective in tracking caribou, and the best option in applying landsat or other imagery is to use predictive habitat models derived from gps tracking, or directly utilize gps tracking. Landsat based landscape classification provides a very good basis for where to go looking for ...


1

You can create borders by using Polygon to Line tool for each polygon. Then use Near tool on these two borders.



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