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11

You can use GRASS GIS for this which supports texture extraction and image classification based on a radiometric/segmentation approach. For an idea, check this conference abstract, a planned talk at the Geoinformatics FCE CTU 2011. See also: http://grass.osgeo.org/wiki/Image_processing and http://grass.osgeo.org/wiki/Image_classification for an overview.


7

I poked around on the State of Hawaii GIS site but most of the layers were too general or too old. The NOAA Coastal Services Center has some Landsat ETM derived land-cover data for Hawaii. There's also some 2.4m Quickbird-derived land-cover data for all islands except the Big Island. Hope that helps!


5

Split tools has an error in ArcGIS 10 SP2. The tool makes the split, but leaves all features empty. Esri was registered this error and recommends for now, if you want use the split tool, downgrade ArcGIS to SP1. I suggest you visit this link http://resources.arcgis.com/es/gallery/file/geoprocessing/details?entryID=6C5D9A77-1422-2418-7F6C-01564409B1AF , where ...


5

Creating landuse database, you need sensor technologies to detect and classify objects. i think you already know that: There are two main types of remote sensing: passive remote sensing and active remote sensing. Passive sensors detect natural radiation that is emitted or reflected by the object or surrounding areas. Reflected sunlight is the most ...


5

To simplify the raster it might be worth looking at gdal_sieve, it's available under the "Raster" menu. See: http://www.gdal.org/gdal_sieve.html N.


4

It does vary by Country - Turkey is poor because the data they used is minimal. For France, Germany, UK, Ireland the data accuracy is vastly better. If you want the accepted paper on the project "The Corine Land Cover (CLC2000) database received a thumbs up for accuracy from an assessment of the project, details of which were released by the EEA today. ...


4

If I understand you correctly, you are looking for a supervised classification procedure. Some theoretical background: http://rst.gsfc.nasa.gov/Sect1/Sect1_17.html This is certainly possible through grass: http://grass.osgeo.org/wiki/Image_classification#Supervised_classification_2 As an alternative you could also look at saga (I'm not saying it is better, ...


4

there are lots of method for calculating land use change in gis systems. if you want to use Arcgis, you should check out Confusion Matrix Analysis for your work. with confusion matrix you can also measure urban sprawl, too.. it is of course necessary to do some research. Wikipedia defination: In the field of artificial intelligence, a confusion matrix ...


4

To generalize, try running a majority filter. This is available in saga (and grass as well, check markusN his answer). An explanation for how it works from arcgis: http://edndoc.esri.com/arcobjects/9.2/net/shared/geoprocessing/spatial_analyst_tools/majority_filter.htm


4

The only high resolution global land cover that I know is the one done by the PR of China. In Europe they seemed to use CORINE as an ancillary data, so it is difficult to judge the consistency accross the world, but it has a spatial resolution of 30 m. http://www.globallandcover.com/GLC30Download/index.aspx http://unstats.un.org/unsd/default.htm You ...


3

As Aragon correctly points out, there are many options for detecting changes in land use using GIS. Before starting, it's worth being aware of the differences between land USE and land COVER, see here for a helpful explanation (it's certainly a distinction that you'll want to make in your dissertation). In addition, bare in mind that any data that you ...


3

Within the US you can obtain detailed soil data from NRCS. For vegetation, check out the GAP data.


3

You can first use the "mode" operator of r.neighbors in GRASS GIS (via Sextante plugin), then vectorize with r.to.vect to obtain polygons. Perhaps the "mode" operator should be run more than one time.


3

Slight correction to a previous answer... NOAA's Coastal Services Center now has 2.4 meter land cover data for all eight of the main islands of Hawaii. Here is the link to the Coastal Change Analysis Program (CCAP) high-resolution land cover download page: http://www.csc.noaa.gov/digitalcoast/data/ccaphighres/download.html Select from the drop down menu ...


3

you can use gdal_polygonize.py for converting raster to vector, if u previously use . some information is here. produces a polygon feature layer from a raster SYNOPSIS gdal_polygonize.py [-o name=value] [-nomask] [-mask filename] raster_file [-b band] [-q] [-f ogr_format] out_file [layer] [fieldname] beside this in qgis ...


3

Kitex You could do a SQL Select that would calculate the areas. MapInfo Professional also has a built-in ProportionOverlap() function that could be used to calculate the proportion/percentage. Select BORDER.ID, CartesianArea(Overlap(BORDER.OBJ, COVERAGE.OBJ), "sq m") "Overlap" , ProportionOverlap(BORDER.OBJ, COVERAGE.OBJ) "PropOverlap" From BORDER, ...


3

You can find Global Land Cover 2000 dataset produced by JRC (an EU organization) http://bioval.jrc.ec.europa.eu/products/glc2000/products.php


3

The FAO released the GLC-Share which provides a set of major thematic land cover layers resulting by a combination of “best available” high resolution national, regional and/or sub-national land cover databases. Metadata and download link here: http://www.fao.org/geonetwork/srv/en/main.home?uuid=ba4526fd-cdbf-4028-a1bd-5a559c4bff38 Remind that both this, ...


3

There is a considerable body of literature on individual crown detection in spectral and lidar data. Methods wise, perhaps start with: Falkowski, M.J., A.M.S. Smith, P.E. Gessler, A.T. Hudak, L.A. Vierling and J.S. Evans. (2008). The influence of conifer forest canopy cover on the accuracy of two individual tree measurement algorithms using lidar data. ...


3

As discovered in the comments, one row (value = 21) was selected before running Reclassify. The Reclassify tool only considered the selected row, therefore only reclassified those pixels where value = 21, to the new value, 2. Edit: it may be worth noting that there is no mention of whether Reclassify respects selections in the help page. I would be ...


2

There are several global land cover products. Globcover, from ESA, is the one (I think) with the best resolution - 300m. It has a fairly detailed nomenclature based on FAO's classification system. Also, if your AOI is in Europe, you can get CORINE Land Cover - a Land Use/Land Cover vector Map for Europe with 25ha of Minimum Mapping Unit and 44 classes of ...


2

If your study area is within the conterminous United States, you might be interested in the National Land Cover Database (NLCD); the latest data is from 2006, and is at a 30-meter resolution.


2

Fairly easy to find in the national dataset. I really like the way it works also. Glovis EarthExplorer


2

We've got some NLCD 2001 data from the USGS on WeoGeo. http://market.weogeo.com/datasets/open_nlcd_2001_hawaii_land_co.html If you look at all the land cover data we have for Hawaii, you may see something you need: http://market.weogeo.com/?query=Land%20cover&lat=20.46&lon=-157.505&zoom=7&layers=BT We've got hundreds of mostly free land ...


2

You would be able to do that with GRASS. You will first work with raster data : I will point you out to that tutorial. See the raster part. You will use r.mapcalc and r.reclass to extract desired features. r.to.vect will permit you to vectorize your data. Finally you will manipulate vector data. v.db.select and v.class will help you.


2

I came across the Global Land Cover Facility from the University of Maryland while searching for stereo satellite image sets.


2

The accuracy of the pan-European forest map 2000 was assesed using the LUCAS2001 dataset. More details here


2

LUCAS This data is available in Vector and Raster Format here: http://www.eea.europa.eu/themes/landuse/interactive/clc-download This data was included in the Open Street Map Project: http://wiki.openstreetmap.org/wiki/WikiProject_Corine_Land_Cover more detail http://wiki.openstreetmap.org/wiki/Corine_Land_Cover RAMON is another that is Combined ...


2

NOTES (these notes are subsidies, not a "complete answer", I need YOUR answer!). I have something, but no reliable sources/references, neither bether clues or confirmations... Do you have sources? Geometrical principles: Points with POSTCODE defined: there are two ways to define georrefered points of POSTCODES, 1.1. by postal address: addresses ...



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