Geographical problems of the second house

The growth rate of the recreation process is discussed. The process manifests itself, among others, in the inhabiting, transportation, production and services. The arising stress results from a relative stability of the material objects and the area designed for recreational use, and from the variability of recreational process. The preferable form of recreation is another dwelling. This manifests itself in the huge migration of urban population to the places for their rest; the extent of this migration depends upon the possession of recreation facilities of a permanent nature such a „huts” or „recreation village houses” that emerged from transformations of the former rural buildings as recreation cottages. Within this mutual interaction between the city and the village there are also trails that lead to the rest sites and to the second dwelling, along which the migrants travel. These trails are a natural result of influence of the city. In this approach the city is a vast integrate, within the variable boundaries of which man accomplishes his needs for recreation and for a second dwelling. The recreational migrations are not merely limited to the inhabitants of large cities. The recreant in the natural environment he seeks is not, like his ancestors, its master but a consumer that often acts as a destructive factor, from which a paradoxal issue results of the nature protection against man but, at the same time, for man. Major traits of the development until now of the second dwelling establishing process in the Socialist Republic of Czechoslovakia, and the perspectives for possible transformations are outlined

Time evolution of a quantum soliton in a Kerr medium

The Q-function of the quantum soliton in a fibre is derived in a new form suitable for the assessment of the possibilities for experimental observations of specific quantum-soliton effects. The characteristic effects of soliton evolution are associated with a cubic term in the nonlinear phase angle and appear at distances well beyond the attenuation length (long range). At the accessible distances, the nonlinear dynamics of a fundamental soliton follows essentially the single-mode dynamics (short and middle range). However, for the higher-order solitons, the form of the evolution parameter suggests strong deviations of soliton dynamics from the single-mode with a square of soliton number. The use of enhanced-nonlinearity fibres and higher-order solitons might make the experimental studies of the specific quantum-soliton features more viable.Natalia Korolkova, Rodney Loudon, Gerlinde Gardavsky, Murray W. Hamilton and Gerd Leuch