Migration is an important aspect of human society. It has existed throughout history, but in modern times it takes a new form. We propose a new approach to the world migration phenomenon as two complex directed networks (immigration and emigration) were countries represents network nodes, and...

Construction initiation (CI) of floor area is an important socioeconomic and physical characteristic of urban structure and its evolution. Despite its importance and the availability of CI data, it has not attracted significant attention until now. Since the 1970s, the Tel Aviv-Yafo Municipality...

Small angle neutron scattering of polyacrylamide solutions and gels is presented for different polymer and cross link concentrations. The gels are analyzed in connection with their elastic properties. For less than 11% of polymer concentration and for small cross link contents c <Subscript>x</Subscript>, it was found...</subscript>

A variant of the Eden model with noise reduction is presented. A site is occupied if it is visited p times but the neighboring sites are added to the potential sites not after occupancy but immediately after the first visit. It results in aggregates with a very different pattern from that of...

We propose a simulation of the underground railway network of Paris which has an apparent fractal dimension equal to 1.8. We show that it is very likely that this value is due to a finite size effect and that the true dimension is 2. This means that caution is necessary in using the concept of...

This paper presents an analysis of the spatial and temporal development of Tel-Aviv. The central notion in the analysis is the old concept of leap-frogging. Instead of seeing the population's evolution as a growth process from the centre of the metropolis outwards, we consider the population's...

We present an application of a growth model for a system of cities. This computer model simulates the evolution of systems with measurable entities (e.g. city size), and takes into account the growth of the entities in terms of size and number. It includes a random multiplicative process for...