We consider front propagation problems for forced mean curvature flows with a transport term and their phase field variants that take place in stratified media, i.e., heterogeneous media whose characteristics do not vary in one direction. We provide a convergence result relating asymptotic in time front propagation in the diffuse interface case to that in the sharp interface case, for suitably ...

The concept of runs, i.e. maximal periodicity or maximal occurrence of repetitions, coined by Iliopoulos et al. [10] when analysing Fibanacci words, has been introduced to represent in a succinct manner all occurrences of repetitions in a word. It is known that there are only O(n) many of them in a word of length n from Kolpakov and Kucherov [11] who proved it in a non-constructive manner. The ...

In this paper we study a model for phase segregation consisting in a sistem of a partial and an ordinary differential equation. By a careful definition of maximal solution to the latter equation, this system reduces to an Allen-Cahn equation with a memory term. Global existence and uniqueness of a smooth solution are proven and a characterization of the ω-limit set is given.

It is a pleasure to be lecturing at the World Bank today. As it happens, the Bank has entered my life at several points. One of my most remarkable teachers was Paul Rosenstein-Rodan. He was among the earliest two economists of great distinction --the other being Sir Alec Cairncross who joined the Economic Development Institute at its founding --to have worked at the Bank. This was between his c...

The fi rst phase of the Community Child Care Research Project consisted of gathering information about the child care contexts of four Indiana communities: Marion, Lake, Allen, and St. Joseph counties. To provide an initial picture of these four communities in relation to child care, we examined existing community data and child care indicators available for the communities, conducted qualitati...

Regional push derives from the geographic agglomeration of economic activities, and is expressed in increments to national productivity. Various pieces of statistical evidence in favour of the existence of regional push effects in lowand middle-income economies are marshalled. The origins of these effects in different sorts of externalities and increasing returns to agglomerative scale and scop...

During the past decade New Zealand has introduced far-reaching reforms in the structure and operation of government departments and agencies. This model has attracted interest in developing countries because it promises significant gains in operational efficiency. But developing countries, which are dominated by informal markets, are risky candidates for applying the New Zealand model. The auth...