24.02.2013 Views

Rudarski radovi br 4 2011 - Institut za rudarstvo i metalurgiju Bor

Rudarski radovi br 4 2011 - Institut za rudarstvo i metalurgiju Bor

Rudarski radovi br 4 2011 - Institut za rudarstvo i metalurgiju Bor

SHOW MORE
SHOW LESS

Create successful ePaper yourself

Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.

μ ( x)<<strong>br</strong> />

=<<strong>br</strong> />

B<<strong>br</strong> />

⎧ y − 8, 8 ≤ y ≤ 9 ⎫<<strong>br</strong> />

⎨ ⎬<<strong>br</strong> />

⎩ − y + 10, 9 ≤ x ≤ 10 ⎭<<strong>br</strong> />

Odrediti: C = A+ B<<strong>br</strong> />

Da bi izvršili naznačene operacije nad<<strong>br</strong> />

datim trougaonim fuzzy <strong>br</strong>ojevima potrebno<<strong>br</strong> />

je odrediti levu i desnu granicu intervala<<strong>br</strong> />

poverenja <strong>za</strong> svaki nivo uverenja<<strong>br</strong> />

α ∈[<<strong>br</strong> />

0,<<strong>br</strong> />

1]<<strong>br</strong> />

. Drugim rečima potrebno je<<strong>br</strong> />

odrediti ekstremne vrednosti u α preseku<<strong>br</strong> />

fuzzy <strong>br</strong>ojeva A i B.<<strong>br</strong> />

Leva granična vrednost fuzzy <strong>br</strong>oja<<strong>br</strong> />

A <strong>za</strong> nivo uverenja α ∈[<<strong>br</strong> />

0,<<strong>br</strong> />

1]<<strong>br</strong> />

dobija se<<strong>br</strong> />

prema izrazu α x L :<<strong>br</strong> />

1<<strong>br</strong> />

x α α α<<strong>br</strong> />

L − 3 = → xL<<strong>br</strong> />

= 6 + 2α<<strong>br</strong> />

2<<strong>br</strong> />

Desna granična vrednost fuzzy <strong>br</strong>oja<<strong>br</strong> />

A <strong>za</strong> nivo uverenja [ ] α α ∈ 0 , 1 ⋅ xR<<strong>br</strong> />

dobija<<strong>br</strong> />

se prema izrazu :<<strong>br</strong> />

1 α<<strong>br</strong> />

α<<strong>br</strong> />

− x R + 5 = α → xR<<strong>br</strong> />

= 10 − 2α<<strong>br</strong> />

2<<strong>br</strong> />

α presek fazi <strong>br</strong>oja je :<<strong>br</strong> />

1 [ α α<<strong>br</strong> />

α = L , R ] = [ 6 + 2α<<strong>br</strong> />

, 10 − 2α<<strong>br</strong> />

]<<strong>br</strong> />

2<<strong>br</strong> />

x x A<<strong>br</strong> />

Analogno prethodnom dobijamo <strong>za</strong> α<<strong>br</strong> />

presek fuzzy <strong>br</strong>oja B :<<strong>br</strong> />

Na sličan način se računa i razlika,<<strong>br</strong> />

proizvod i količnik fuzzy <strong>br</strong>ojeva.<<strong>br</strong> />

Ako su aktivnosti Ai, čije je trajanje ti<<strong>br</strong> />

fuzzy <strong>br</strong>oj, prika<strong>za</strong>ne pomoću krugova ili<<strong>br</strong> />

Sl. 2. Fuzzy <strong>br</strong>ojevi A, B, C<<strong>br</strong> />

[ α α<<strong>br</strong> />

y ] = [ 8 + α,<<strong>br</strong> />

− α ]<<strong>br</strong> />

B α = L , yR<<strong>br</strong> />

10<<strong>br</strong> />

Izračunajmo zbir fuzzy <strong>br</strong>ojeva A i B<<strong>br</strong> />

koji je označen sa C . Fuzzy <strong>br</strong>oj C se<<strong>br</strong> />

formalno <strong>za</strong>pisuje C = { z, μ ( z)<<strong>br</strong> />

} .<<strong>br</strong> />

C<<strong>br</strong> />

Prema pravilu o sabiranju trouglastih<<strong>br</strong> />

fuzzy <strong>br</strong>ojeva sledi:<<strong>br</strong> />

C = [ (6 + 2 α) + (8 + α),(10- α) + (10 − 2α]<<strong>br</strong> />

=<<strong>br</strong> />

= [ 14 + 3 α,20 −3α]<<strong>br</strong> />

Jednačine koje predstavljaju levu i<<strong>br</strong> />

desnu stranu fuzzy <strong>br</strong>oja C:<<strong>br</strong> />

α 1 α 14<<strong>br</strong> />

14 + 3α<<strong>br</strong> />

= z → α = z −<<strong>br</strong> />

3 3<<strong>br</strong> />

α 1 α 20<<strong>br</strong> />

20 − 3α<<strong>br</strong> />

= z → α = − z −<<strong>br</strong> />

3 3<<strong>br</strong> />

Funkcija pripadnosti fuzzy <strong>br</strong>oja C je<<strong>br</strong> />

takođe oblika trougla i formalno se predstavlja<<strong>br</strong> />

analitičkim izrazom:<<strong>br</strong> />

⎧ 1 14 ⎫<<strong>br</strong> />

z − , 14 ≤ z ≤ 17<<strong>br</strong> />

⎪ 3 3<<strong>br</strong> />

⎪<<strong>br</strong> />

μ ( z ) =<<strong>br</strong> />

C ⎨ ⎬<<strong>br</strong> />

⎪ 1 20<<strong>br</strong> />

− z + , 17 ≤ z ≤ 20 ⎪<<strong>br</strong> />

⎪⎩ 3 3<<strong>br</strong> />

⎪⎭<<strong>br</strong> />

A i B Fuzzy <strong>br</strong>ojevi kao i njihov zbir, tj.<<strong>br</strong> />

fuzzy <strong>br</strong>oj C prika<strong>za</strong>ni su na slici 2.<<strong>br</strong> />

pravougaonika (precedence dijagram),<<strong>br</strong> />

onda se vremena njihovih najranijih i najkasnijih<<strong>br</strong> />

<strong>za</strong>vršetaka RZi I RKi izračunavaju<<strong>br</strong> />

pomoću sledećih izra<strong>za</strong>:<<strong>br</strong> />

Broj 4,<strong>2011</strong>. 150<<strong>br</strong> />

RUDARSKI RADOVI

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!