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liyi
Navier-Stokes Equations
Navier-Stokes Equations

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Joined: 17 Jul 2003
Posts: 1630
Location: Foochow, Fukien
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#1
ask a concept

In an exercise of my book, it defines "weak ring" (literally translated from Chinese) as follows.

(R,+,\cdot) is a weak ring, if it satisfies:
(1) (R,+) is an additive group; (it is abelian)
(2) (R,\cdot) is a semigroup;
(3) There exist fixed elements e_1,e_2 such that
x(y+z)=xy+xz-e_1 and (y+z)x=yx+zx-e_2 for all x,y,z\in R.


I cannot find such a name on internet...
Is it a special ring? Or just an exercise?

PostPosted: Wed Feb 09, 2005 1:23 am  Back to top 
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Thomson
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New Member

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Joined: 23 Jul 2004
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Location: San Diego
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#2
I think this might be called a semiring...here's a link:

http://mathworld.wolfram.com/Semiring.html

PostPosted: Fri Feb 18, 2005 1:22 am  Back to top 
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liyi
Navier-Stokes Equations
Navier-Stokes Equations

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Joined: 17 Jul 2003
Posts: 1630
Location: Foochow, Fukien
China

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#3
It isn't. The distributivity is different.

PostPosted: Fri Feb 18, 2005 2:00 am  Back to top 
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