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What should be done about <math>\sigma</math>? --Rick 12:43, 15 June 2007 (CDT)

And K? Where did this first get used as partitioning ratio & do others use something else? --Rick 13:48, 15 June 2007 (CDT)
Resolved. --Chris Booth 11:57, 19 June 2007 (CDT)


We could have consistent and logical notation for ratios of any combination of volume/area/number/lengths if we adopt stereological convetnions of <math>X_Y</math>, where X is the numerator & Y is the denominator & they can be replaced by any combination of N, A, N, or L. What about adopting, for example, <math>V_V</math> for volume fraction? --Rick 13:21, 15 June 2007 (CDT)

No. Because Voorhees doesn't do this.--Chris Booth 11:58, 19 June 2007 (CDT)

Number Density Coarsening Constant

Chris uses <math>A_{KV}</math> as the prefactor in the number density coarsening equation. A has been used as a "throw-away" prefactor in the past (for creep, conductivity, etc.--any place where we don't care much about it). Since (as far as I know) we invented this notation, do we want to assign something more permanent? --Rick 13:55, 15 June 2007 (CDT)

It is best to eliminate <math>A_{KV}</math> and simply use the notation given by Voorhees in his coarsening equations.

Mean Planar Radius

Excerpt from conversation with CKS:

The precipitation strengthening community (including both Ardell and Nembach) generally use



 $\langle r \rangle$

DNS converted us to:

 $\langle R \rangle$

and, after MUCH debate, the Al people settled on


If you want to change it, you may have a fight with Keith! That might be one of the things that really sparked creation of that wiki page two years ago & was one of his first rants about notation.

While I use Keith's notation, I personally think \bar{R} and R_{PS} are both ugly as sin. I plan to use KEK's notation until we find a mutual compromise or until DNS asks me to change. Since we might be able to change this quantity, perhaps R^{2D} or R_A (the former being similar to the interppt paper's notation & the latter being similar to notation used by stereology (A is area)?

Do they use subscript PS for any other quantity? Is there a way that they differentiate between something that is directly measured from cross sections vs. that which is converted from the 3D <R>?

Because of the LEAP (and, for some of us, because of the ppts are small w.r.t a TEM foil), we often measure <R> directly and must convert to a planar radius to calculate interactions in a glide plane, etc. This differs from SEM work, of course. --Rick 14:19, 15 June 2007 (CDT)

To discuss. --Chris Booth 11:58, 19 June 2007 (CDT)


All have latin and greek symbols:

  • Bulk modulus: K, <math>\chi</math>
  • Shear modulus: G, <math>\mu</math>
  • Young's elastic modulus: E, <math>\gamma</math>

There is more overlap in the latin (K being coarsening a coefficient & G being Gibbs Free Energy). While there's a wrinkle that some popular alloy systems hava a gamma pgase, perhaps we should use greek for ALL of these? --Rick 14:33, 15 June 2007 (CDT)

We'll use latin for everything after removing some overlapping notation. --Chris Booth 11:51, 19 June 2007 (CDT)

Atomic volume

RPK uses Omega for atomic volume of alloy, but V_a is used (particularly for phase-specific volume V_a^i). We should resolve this. --Chris Booth 11:51, 19 June 2007 (CDT)

The group has published extensively using Omega for atomic volume. It is also the notation used in Miller's book. -- Prakash 1:48 19 June 2007

Other nomenclature

While ppt=precipitate; mat=matrix; int=interface, this notation will generally be expanded by DNS for legibility. --Chris Booth 11:34, 19 June 2007 (CDT)

APFIM = atom-probe field-ion microscopy. However, this is essentially the same as APT & won't be heavily used. --Chris Booth 11:36, 19 June 2007 (CDT)

RPK uses N_{atoms} for number of atoms. In what context? How is it different than N_{0} or N_{i,j,k} (for types of atoms) --Chris Booth 11:44, 19 June 2007 (CDT)

<math>N_{atoms}</math> is a user defined parameter used in the envelope method. It goes along with <math>d_{max}</math>. It is not related to <math>N_{0}</math> nor <math>N_{i,j,k}</math>. -- Prakash 1:44, 19 June 2007 (CDT)

What to use for confidence threshold. RPK uses the verbose c^{threshold}. --Chris Booth 11:46, 19 June 2007 (CDT)