... | ... | @@ -7,19 +7,19 @@ Once you managed to get photoelastic images of your sample you can either be hap |
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Simple image intensity analysis:
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At order zero, you can simply analyze the average image intensity. You assume that the brighter the larger the stress and with a rough calibration you can get pressure estimation. More details about how to do it are given [here]().
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At order zero, you can simply analyze the average image intensity. You assume that the brighter the larger the stress and with a rough calibration you can get pressure estimation. More details about how to do it are given [here](https://git-xen.lmgc.univ-montp2.fr/PhotoElasticity/Main/wikis/qualitative-analysis).
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Image gradient analysis:
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A more sophisticated method consists in analyzing the intensity of the squared image intensity gradient $`G^2`$ which gives information about the photoelastic fringe density. It has been shown by [Howell *et al.*](https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.82.5241) that this is proportional to the inner pressure. Calibrating the method for your material you can get a quite accurate information about the pressure in you sample. More details about this method are given [here]().
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A more sophisticated method consists in analyzing the intensity of the squared image intensity gradient $`G^2`$ which gives information about the photoelastic fringe density. It has been shown by [Howell *et al.*](https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.82.5241) that this is proportional to the inner pressure. Calibrating the method for your material you can get a quite accurate information about the pressure in you sample. More details about this method are given [here](https://git-xen.lmgc.univ-montp2.fr/PhotoElasticity/Main/wikis/gradient-analysis).
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Inverse problem method:
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There is a last analysis method which give the full mechanical information. In the case where you know the exact geometry of you sample and the material behavior, you can use an inverse problem method to get applied external forces for example. This have been implement in granular matter by [Majmudar and Behringer](https://www.nature.com/articles/nature03805) for example. More details about this method are given [here]().
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There is a last analysis method which give the full mechanical information. In the case where you know the exact geometry of you sample and the material behavior, you can use an inverse problem method to get applied external forces for example. This have been implement in granular matter by [Majmudar and Behringer](https://www.nature.com/articles/nature03805) for example. More details about this method are given [here](https://git-xen.lmgc.univ-montp2.fr/PhotoElasticity/Main/wikis/inverse-analysis).
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[this tutorial](https://git-xen.lmgc.univ-montp2.fr/PhotoElasticity/Main/wikis/molding-gel) |