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In article <50ln1e$514@ces.ces.kyutech.ac.jp>
zhang@ces.ces.kyutech.ac.jp (Hong Zhang) writes:
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> $B@5Dj9TNs&!B2$NCf$N$?$@$N0l$D$G$"$k$H;W$$$^$9!#(B

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n = 4 $B$G@5DjCM$N>r7o$G$b$N$r9M$($k$J$i$P(B

a b 0 0
b c d e
0 d f g
0 e g h

$B$G(B c, d, e, f, g, h $B$r(B (a > 0 $B$O2>Dj$7$F$*$$$F(B)

|a b| = a c - b^2 > 0,
|b c|

|a b 0|
|b c d| = (a c - b^2) e - a d^2 > 0,
|0 d e|

|a b 0 0|
|b c d e| > 0,
|0 d f g|
|0 e g h|

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r s

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 g = 0, f $B$H(B h $B$H$OHsIi(B,

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>    LMI $B$H$O(B Linear Matrix Inequalities$B$N=L<L$G$9!#(BLMI$BM}O@$O(B
> $B@)8f%7%9%F%`$N%Q%i%a!<%?@_7W$K$h$/;H$o$l$F$$$k$h$&$G$9!#(B

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-- 
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Tsukamoto, C. : chiaki@ipc.kit.ac.jp