Dimension reduction in magnetohydrodynamics power generation models: Dimensional analysis and active subspaces

<div>&#160;</div><div> <div> <div>Dimensional analysis offers an ideal playground to tackle complex hydrological problems. The powerful dimension reduction, in terms of governing dimensionless groups, afforded by the PI-theorem and the related self-similarity arguments is especially fruitful in case of nonlinear models and complex datasets. After briefly reviewing these main concepts, in this lecture I will present several applications ranging from hydrologic partitioning (Budyko's curve) and stochastic ecohydrology, to global weathering rates and soil formation, as well as landscape evolution and channelization. Since Copernicus-dot-org asks me to add at least 25 words to the abstract, I would like to thank the colleagues who supported my nomination for the Dalton medal and my many collaborators.</div> </div> </div>

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Reprint of: Active subspaces for sensitivity analysis and dimension reduction of an integrated hydrologic model

Computers & Geosciences ◽

10.1016/j.cageo.2015.11.002 ◽

2016 ◽

Vol 90 ◽

pp. 78-89 ◽

Cited By ~ 12

Author(s):

Jennifer L. Jefferson ◽

James M. Gilbert ◽

Paul G. Constantine ◽

Reed M. Maxwell

Keyword(s):

Sensitivity Analysis ◽

Dimension Reduction ◽

Hydrologic Model ◽

Active Subspaces ◽

Integrated Hydrologic Model

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Hydrology without Dimensions

10.5194/egusphere-egu2020-11883 ◽

2020 ◽

Author(s):

Amilcare Porporato

Keyword(s):

Dimension Reduction ◽

Dimensional Analysis ◽

Landscape Evolution ◽

Nonlinear Models ◽

Soil Formation ◽

Self Similarity ◽

Weathering Rates ◽

Dimensionless Groups ◽

Pi Theorem ◽

S Curve

<p>Dimensional analysis offers an ideal playground to tackle complex hydrological problems. The powerful dimension reduction, in terms of governing dimensionless groups, afforded by PI-theorem and related self-similarity arguments is especially fruitful in case of nonlinear models and complex datasets. After briefly reviewing these main concepts, in this lecture I will present several applications ranging from hydrologic partitioning (Budyko&#8217;s curve) and stochastic ecohydrology, to global weathering rates and soil formation, as well as landscape evolution and channelization.&#160;Since Copernicus-dot-org asks me to add at least 25 words to the abstract, I would like to thank the colleagues who supported my nomination and my many collaborators.</p><p>&#160;</p><p>&#160;</p>

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In situ investigation of the primary recrystallization of alpha titanium in HVEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100110313 ◽

1978 ◽

Vol 36 (1) ◽

pp. 634-635

Author(s):

S. Naka ◽

R. Penelle ◽

R. Valle

Keyword(s):

Dimensional Analysis ◽

Texture Evolution ◽

Cold Work ◽

Three Dimensional ◽

Primary Recrystallization ◽

Thin Foils ◽

In Situ Investigation ◽

Grain Growth Model ◽

Alpha Titanium

The in situ experimentation technique in HVEM seems to be particularly suitable to clarify the processes involved in recrystallization. The material under investigation was unidirectionally cold-rolled titanium of commercial purity. The problem was approached in two different ways. The three-dimensional analysis of textures was used to describe the texture evolution during the primary recrystallization. Observations of bulk-annealed specimens or thin foils annealed in the microscope were also made in order to provide information concerning the mechanisms involved in the formation of new grains. In contrast to the already published work on titanium, this investigation takes into consideration different values of the cold-work ratio, the temperature and the annealing time.Two different models are commonly used to explain the recrystallization textures i.e. the selective grain growth model (Beck) or the oriented nucleation model (Burgers). The three-dimensional analysis of both the rolling and recrystallization textures was performed to identify the mechanismsl involved in the recrystallization of titanium.

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