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E, resp. F , can be either a Euclidean or a dig- E or F having real or ± ∞ values. Here the analog of the cisoid function is the linear function α of slope α defined by l α (x) = hα, xi. For any function f on E one defines its slope transform S ∨ (f ) and its lower slope trans- form S ∧ (f ) by S ∨ (f )(α) = sup x∈E f (x) − hα, xi and S ∧ (f )(α) = inf x∈E f (x) − hα, xi . The counterpart for dilations and erosions of S ∨ (f ⊕ g) = S ∨ (f ) + S ∨ (g) and S ∧ (f g) = S ∧ (f ) − S ∨ (g). For any function ψ on F one defines the ad- joint upper slope transform S − ∨ (ψ) and the adjoint lower slope transform S − ∧ (ψ) by S − ∨ (ψ)(x) = inf α∈F ψ(α) + hα, xi and S − ∧ (ψ)(x) = sup α∈F ψ(α) + hα, xi . Contrarily to the Fourier inversion formula f on E, S − ∨ (S ∨ (f )) is the concave hull of f , in other words the lower envelope of all linear functions α + c (α ∈ F , c real) which are ≥ f , while S − ∧ (S ∧ (f )) is the convex hull of f , in other words the upper envelope of l α + c which are ≤ f . See There is a variant theory of slope trans- forms„ where S − ∨ (f ) is a multivalued func- tion, and for which an exact inverse transform slot a space between the teeth used to place windings in electrical machines. slot pitch the angular distance (normally in electrical degrees) between the axes of two slotless motor permanent magnet brush- less DC motor in which stator teeth are re- slotted ALOHA a multiple access proto- col. In slotted ALOHA, time is divided into slotted line coax or waveguide with a lon- gitudinal slot that accommodates a voltage slow start a congestion control algorithm that rapidly determines the bandwidth avail- slow wave a wave whose phase velocity is slower than the velocity of light. For ex- c 2000 by CRC Press LLC |