Let r > 0 be a finite delay and C0 = C([−r, 0], H) the Banach space of continuous vector-valued functions defined on [−r, 0] taking values in a real separable Hilbert space H. This paper is concerned… (More)

We consider the following new differential inclusion −du ∈ NC(t)(u(t)) + F (t, u(t)) , where u : [0, T ] → IR is a right-continuous function with bounded variation and du is its Stieltjes measure;… (More)

(1.2) C(t, u) ⊂ H is nonempty, closed, and convex for t ∈ [0, T ], u ∈ H. In (1.1), NC(t,u)(x) denotes the normal cone to C(t, u) at x ∈ C(t, u), cf. Section 2 below. We will treat the case of (t, u)… (More)

Candido Portinari (1903–1962) is the most famous Brazilian painter, whose production of more than 4500 works is spread all over the world. We are currently undertaking the design and production of… (More)

This technique of approximation is not new; see, e.g., [6], [13], [14]. Since a tangency condition involving F and a tangent cone, say T , leads to a tangency condition involving Fh and conv T , in… (More)

We prove existence theorems for evolution equations of the form −u(t) ∈ ∂δC(t)(Au(t)) with some maximal monotone and strongly monotone operator A : D(A)→ 2 . 1 – Introduction and main results We… (More)

After defining some demographic indicators, the author develops a theory of reduced events and attempts to illustrate the impact of changes in the intensity and timing of demographic phenomena. A… (More)

We consider the one-dimensional dynamics of a particle moving on a mobile plane with contact being kept and dry friction. The particle is submitted to normal loading described not only by usual… (More)

The methodology of making population projections is discussed, with particular reference to Portugal. Consideration is given to ways in which migration is included in such projections. The data used… (More)