Comments (12)
The only reference is Coscia et al. (2011) in equation (2):
Coscia, I., Greenhalgh, S., Linde, N., Doetsch, J. A., Marescot, L., Günther, T., Vogt, T. & Green, A. (2011): 3D crosshole ERT for aquifer characterization and monitoring of infiltrating river water. Geophysics 76(2), G49-G59, doi:10.1190/1.3553003.
from gimli.
Thank You Sir
from gimli.
May I ask, which reference you followed for lambda regularization?
from gimli.
Regularization is explained in more detail in the tutorial https://www.pygimli.org/_tutorials_auto/3_inversion/plot_5_Regularization.html
from gimli.
Thanks, yes I followed that. Is there any research article specifically explaining the regularization mentioned in the tutorial. Especially the smoothness constraint matrices considered for unstructured mesh.
from gimli.
For regularization of , we refer to Günther et al. (2006), the foundation is in more detail explained in Günther (2004) and some other details you can find in Coscia et al. (2011).
Günther, T., Rücker, C. & Spitzer, K. (2006): Three-dimensional modeling and inversion of dc resistivity data incorporating topography – II: Inversion. Geophys. J. Int. 166, 506-517, doi:10.1111/j.1365-246X.2006.03011.x.
Günther, T. (2004): Inversion Methods and Resolution Analysis for the 2D/3D Reconstruction of Resistivity Structures from DC Measurements. PhD thesis, University of Mining and Technology, Freiberg, available on http://nbn-resolving.de/urn:nbn:de:swb:105-4152277.
Coscia, I., Greenhalgh, S., Linde, N., Doetsch, J. A., Marescot, L., Günther, T., Vogt, T. & Green, A. (2011): 3D crosshole ERT for aquifer characterization and monitoring of infiltrating river water. Geophysics 76(2), G49-G59, doi:10.1190/1.3553003.
from gimli.
What is the recommended approach to choose zWeight
in inversion?
from gimli.
There is no formal approach. The value expresses the expectation to the subsurface, on how much the resistivity varies in the horizontal and vertical directions. This can be between 1 (or even above in rare cases of vertical structures) and low values like 0.1 or 0.01 for strongly layered structures.
from gimli.
What is zWeight
in the context of seismic tomography? Just like resistivity range, what could be the possible range in traveltime tomography?
from gimli.
The parameter controls the regularization, no matter which parameter is inverted. Wasn't this obvious? Please read the tutorials on regularization.
from gimli.
Actually, I was trying to find what values can be given. However, document didn't mention or I didn't find it that it should be in between 0 and 1
, not like regularization parameter \lambda
. Even while running inversion, giving any value higher than 1 is not throwing any warning or error.
Am I right that zWeight
need to be in the range of 0 to 1?
from gimli.
There is no need to be between 0 and 1. As I explained in my above comment, it can be very reasonably above 1 and of course it can formally also below 0 regarding formula (2) in Coscia et al. (2011). However, if the weight falls below 0, the contribution to the smoothness rises again and there will be a direction with minimum smoothness. So, in fact values below (or even equal to) zero do not make sense although they are possible.
from gimli.
Related Issues (20)
- how to fix import pygimli error libcholmod.so.3 on Mybinder HOT 9
- Plot Inversion Result from Another Software use Pygimli HOT 2
- fitReciprocalErrorModel IP data HOT 7
- Seeking Help with 3D Magnetic Inversion HOT 2
- Question about geometric factor for an ERT survey with submerged and terrestrial electrodes HOT 4
- ERTManager.invert() --> error: malloc(): unsorted double linked list corrupted HOT 4
- Failure to install on mac HOT 6
- Wrong coordinates in tutorial notebook HOT 4
- pyGIMLi and NUM_THREADS HOT 7
- 3d geometry with topography and fixed thin layer HOT 5
- pg.interpolate() giving error with regionwise regularization HOT 8
- Discussion regarding `errorVals`-`absoluteError`-`relativeError` HOT 4
- Petrophysical joint inversion: smooth the output result HOT 3
- Running pyGIMLi on GHA fails to import HOT 3
- Can the gimli module perform joint HVSR-Dispersion Curve inversion? HOT 2
- The resistivity values are inverted after inversion with dipole-dipole array HOT 9
- Matplotlib version >3.8.4 causes failure to load module HOT 5
- colab and /tmp HOT 3
- Marker in the Model is not readable in the final result HOT 2
- Coupled DC-Magnetic Inversion HOT 6
Recommend Projects
-
React
A declarative, efficient, and flexible JavaScript library for building user interfaces.
-
Vue.js
🖖 Vue.js is a progressive, incrementally-adoptable JavaScript framework for building UI on the web.
-
Typescript
TypeScript is a superset of JavaScript that compiles to clean JavaScript output.
-
TensorFlow
An Open Source Machine Learning Framework for Everyone
-
Django
The Web framework for perfectionists with deadlines.
-
Laravel
A PHP framework for web artisans
-
D3
Bring data to life with SVG, Canvas and HTML. 📊📈🎉
-
Recommend Topics
-
javascript
JavaScript (JS) is a lightweight interpreted programming language with first-class functions.
-
web
Some thing interesting about web. New door for the world.
-
server
A server is a program made to process requests and deliver data to clients.
-
Machine learning
Machine learning is a way of modeling and interpreting data that allows a piece of software to respond intelligently.
-
Visualization
Some thing interesting about visualization, use data art
-
Game
Some thing interesting about game, make everyone happy.
Recommend Org
-
Facebook
We are working to build community through open source technology. NB: members must have two-factor auth.
-
Microsoft
Open source projects and samples from Microsoft.
-
Google
Google ❤️ Open Source for everyone.
-
Alibaba
Alibaba Open Source for everyone
-
D3
Data-Driven Documents codes.
-
Tencent
China tencent open source team.
from gimli.