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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 ...


4

from GRASS GIS: v.buffer: -c Don't make caps at the ends of polylines from the interface of v.buffer.distance in QGIS (Processing Toolbox): from the interface of v.buffer.column in QGIS (Processing Toolbox): or use GRASS GIS directly and not the GRASS plugin (as says zimmi)


4

You can use Data Driven Pages to quickly loop through each feature of your feature class. Within the settings you can set up what % you want to zoom to - i.e. 100% will have the feature fill the screen, but you might want to try something like 150%. This tool, although designed to make maps, is also useful for inspecting features quickly.


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

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: ...


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

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

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

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 ...


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

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

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.


1

The arcpy way of doing this would be the following logic: Referencing Gerry Gabrisch Create Perpendicular Lines to Each Segment of a Shapefile and this Q/A you can create perpendiclar transects at the start and end point of each line segement. The transect feature class may then be used to split the buffered layer using the python logic that @iRfAn has ...


1

You could use GRASS itself because it exposes the -c option.



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