C. La-covariance, (h) peut être mesurée de manière directionnelle : C(h) = P { x?A, x+h ?A } pour tout x ?D et h fixé dans une direction

. De-la-même-manière, nous pouvons aussi mesurer la covariance de la matrice Q(h), qui en pratique sert pour le choix d'un modèle aléatoire: Q(h) = P { x? A c

@. Détection-de-la-façon-dont-l-'ensemble and A. Distribué, Par exemple, cela revient à détecter si les grains qui constituent un matériau sont distribués de façon aléatoire ou périodique : si périodicité il y a, elle doit se retrouver dans les courbes de covariance. La fraction surfacique après érosion de la matrice par un segment

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