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Hi Steve, thanks for your input. I created a workaround First i refined the mesh-resulution in FEFLOW a bit and made a second calculation Then I imported the FEFLOW-Results als Shapefile (see original post above) and again did the Points-to-raster Operation, leading to a similar result as in my first post (I set the cellsize to 5 m): But what I then did was applying a low-pass filter to reduce the "noise". Not just one to be honest, 6 in a row. the result was this: This is as close as it gets to the FEFLOW-Plot. Just for comparison, this is the IDW-Result: Not quite as nice, right? Cheers Oliver
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08-14-2019
08:51 AM
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Hello world! I'm facing a pretty frustrating task atm. For the straight-forward guys: my questions are in the very end. For anyone interested in further details, here some screenshots. Here the result of a hydrological simulation using the software FEFLOW (finite-element): What it shows is the temperature distribution in groundwater-offstream of geothermal injection wells. So far so good, result is not only valid, but looks real good.ull The problem now is to export that result as raster for further use in ArcGIS, which is not possible using that software. It allows me only to export the values on the node-points I used to create the distribution. So, it is possible to export as Shapefile, but when importing it to Arcgis, it of course looks like that: You might now already know what my problem is.... I now need to find a way to convert it into a raster. Interpolation (Kriging, IDW etc.) leads to horrible results, I've tried that already. It also seems riddiculous to again krig the result of a precice FE-model.... My way was the tool "Points to raster". I'm feeling that I'm on the right way, but am still facing a problem, that you'll see in the following screenshot: You see, this is no comparison to the first screenshot (FEFLOW-model) My questions to you now: 1 Is there a way to further edit that raster above, to get full coverage (no gaps) with some kind of nearest-neighbor operation? 2 Is there another way of working with that data in ArcGIS, to create a raster as good as the simulation-result in FEFLOW? 3 What would you do (Feflow allows exporting in .xlsx, .accdb, .dbf, .dxf, .mdb, .pnt, .trp .dat and .shp) but none of those would give me a better feeling...
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08-13-2019
12:45 AM
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That gives me a very positive feeling. Next step ist the interpolation of permeability-values. That probably won't go so well, but let's see Thanks a lot for your advice!
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03-15-2019
01:36 AM
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Hi Eric, thanks for your answer! I only need predicted values and focus on the center of my interpolated surface (so edge areas are less important). I did a few kriging calculations (about 20 in total) with slightly different parameters, (all Ordinary Kriging, mostly with exponential or gaussian function) for the beginning and well, my errors do not differ a lot. My RMS ranges between 0.19 and 0.20 RMSS lies between 0.999 and 1.14 ME ranges between 0.002 and 0.005 "Best" values occur when using exponential kernel function (although I've often read, gaussian is good for groundwater simulations). Nevertheless, all results "look" fine, as they represent the flow-direction, that is commonly known for that area. Differences are small. Considering that, I guess I should probably focus on the simulation with the lowest RMS then. I hope I didn't forget another important point.
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03-14-2019
02:51 AM
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Hi Jim, thanks for your advice. I've thought about this problem a long time and therefore included more datapoints outside of my actual area of interest. So the edges of my prediction-map will not be relevant for my model any more. Considering, that only the center of my Kriging-prediction-map is of interest to me, doesn't that make the described errors (RMS, etc.) more important?
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03-14-2019
02:32 AM
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Hi community, I'm currently trying to find the best and most accurate Kriging-interpolation for my project: interpolation of a groundwater-surface in an unconfined aquifer. My project-area is a city-district of Vienna, Austria. My aquifer is mostly homogenous, consisting of gravel and sand and shows a slight trend of decreasing groundwater-levels in ESE direction. So far, so good. I've now tried "ordinary kriging" with gaussian kernel function and applied different settings (number of sectors, size of lags, etc.). My problem now (please correct me if I'm wrong): For assessing the quality of my results, I focus on the following factors: 1. Root-mean-square (should be as small as possible) 2. Root-mean-square-standardized (should be as close to 1 as possible) 3. Mean standardized error (should be as small as possible) 4. Average standard error (should be as small as possible) Right? But which of these factors is most important? I'm currently facing the problem, that I have cases, in which RMS and MSE are close to 0; RMSS) is close to 1, BUT average standard error is relatively high..... and cases where it is the other way round. And another question: Is Ordinary Kriging a good usable method for modeling groundwater-levels anyway? I also thought about using external drift-Kriging perhaps, but as I'd probably have to use the surface-model as 2nd parameter, it doesn't seem to make sense (urban flat-lands, low natural differences in elevation, where human-caused changes in elevation are probably higher than natural changes).
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03-12-2019
05:23 AM
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The points rotation is based on the direction of the groundwater-flow, which in this area is relatively constant going to SE - ESE, referring to government data. I'm still not sure, whether I shall make the effort and calculate (validate) it by myself (which would require more data and would cause more waiting-time - the mills of my city government grind slowly).
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09-16-2016
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Thanks, that's really what I wanted to know! I actually hoped to be able to avoid Python, but well, I need a refreshment anyway So thanks for your help, I appreciate it a lot! Xander, In attachment are two files. "Strapetz_kf" is the dangerzone. In "targets" the dangerzone is located at one point with the arrows showing where it shall be copied to. This is just a sample. Anyway, I'll try out Rebeccas remarks, so the topic is solved for now Thanks also to you and anyone else, who gave their input.
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09-15-2016
08:58 AM
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Thanks Rebecca, that comes pretty close to what I need. So is it possible then, to define a non-centric x/y point in my polygon (because the source of the dangerzone is not the polygons geometric center) and duplicate it to new x/y-locations, referring to all 100 xy-coordinates of my feature class "pumpingstations"? Xander, I'll upload a sample-image tomorrow, then you'll see what it looks like. All the duplicated polygons will have the same rotation and extent, as the original one has, yes. Thanks again, you're making my life a lot easier atm, helping me with my student-problems
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09-14-2016
12:45 PM
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Hi guys! Thanks for your replies! Well, actually my image contains an exact spatial extend for a zone, which is why I can't use it as a style. I thought about vectorizing it via ArcScan, so I can later create a polygon out of my image, showing the dangerzone as irregular, but almost elliptic shape and then connect it with the pumping-points. There are about 100 pumping-points in my area, and every single one creates the same dangerzone (based on the same pumping capacity). So my shape actually would need to be copied 100 times and connected with the pumping-points, once for each point. To say it as metaphor: Imagine the model of a house. There are 100 properties in my town and every single owner of each property is going to get the exact same house. That's what I want to achieve
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09-14-2016
04:55 AM
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Hello community! I have a special question on georeferencing, on which I haven't yet found an answer. I want to create danger areas for groundwater-pumps. To achieve that, I have a point-shapefile of all the groundwater-pumps in my city, including information of their pumping capacity, the groundwater-flow direction in that area, etc. In addition to that I have created an image in a program called "Processing Shemat", showing the spatial expansion of the pump-related thermal influence in the ground water from one single pumping station. This image was created for one single pumping station, but will look the same for all others, too. So let's assume, that this one graphic is valid for all the points in my shapefile. What I now want to do is importing that image to arcgis and not only connect it with one of the points in my shapefile, but all of the points (so that as result I'll have 1000 images (one per point in my shapefile) instead of only one)? All the tutorials on georeferencing in the internet showed me, how I can adjust that picture to a single point, but doing that for 1000 pumping stations in the city is too much of an effort. So is there a possibility of (sorry for my amateurish language) kind of telling arcgis to connect the image from one point in the picture to all the points in my shapefile? Does that even make sense with a raster, or should I first use ArcScan to vectorize it and make a similar operation later? Thanks in advance for your help
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09-12-2016
11:14 AM
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