Spatial system

Articles

• Discontinuity
  3 December 2004, by J.-C. F.

  In a very broad acceptation, discontinuity is what separates two neighbouring and different spatial sets. One can distinguish the elementary discontinuity, built on a single indicator, which is a useful but frail indication, from the structural discontinuity, superposition of numerous converging elementary discontinuities measured on basis of a coherent set of indicators. The latter may be defined as the spatial form of transition between two neighbouring systems.
  Discontinuity may be (...)

• Spatial system
  12 January 2005, by F.D.-D., L. S.

  A system is a set of sets : set of elements linked with each other through relations which form a set of interactions ; presence of positive and/or negative retro-action loops is an indispensable element of a system definition. Defined in this way, a system forms a totality, whose limits may be defined. Most systems in which human sciences are interested are open; they maintain relations with a part of the outside world which constitutes their environment. Inputs in the system condition its (...)

• Centre/Periphery
  13 October 2004, by C.G.

  The geometrical metaphor of centre and periphery is often used to describe opposition between the two basic types of places in a spatial system : the one which is commanding and benefitting it, the centre, and those which are subjected to it, in a peripheral position. This conceptual pair goes back at least to the time of Werner Sombart (Der moderne Kapitalismus, 1902), if not of Marx (city/countryside relations), and was used by the imperialism theoreticians (Rosa Luxemburg, Boukharine) (...)

• Theories of spatial analysis
  12 January 2005, by D. P.

  The general theoretical position of spatial analysis consists in proposing a partial explanation as well as prediction possibilities about the state and probable evolution of geographical objects / entities, on basis of knowledge of their situation with respect to other geographical objects.
  There exists not yet any general theory of geographical space that could be a theory of concentrations, of spacing, of spatial structures and of evolution of spatial systems, relying on knowledge of (...)

• Discontinuity
  27 July 2009, by J.-C. F.

  In a very wide acceptation, discontinuity is what separates two different, neighbouring spatial ensembles. It is possible to distinguish elementary discontinuity, constructed on the basis of a single indicator, which is a useful but vulnerable indicator; and structural discontinuity, which is the superimposition of numerous elementary, convergent discontinuities that are measured from a coherent set of indicators. This latter type can be defined as the spatial form of the transition between (...)

• Bifurcation
  6 October 2004, by D. P.

  By analogy with the physico-chemical theory of dissipative structures, or with synergetics: in a dynamic system, qualitative change of structure which may be generated by an amplification of a small internal fluctuation or by an external perturbation, when the system is in an unstable state. Bifurcations are theoretically unpredictable, they drive the system toward a configuration whose path may be perfectly determined but which is not the only possible one. This concept allows reconciling (...)

• Resilience
  6 October 2004, by C.A.-L.

  Resilience is a notion originally used in physics in order to designate resistance of a material to shock. In ecology, it takes a different meaning: in its traditional acceptation, it measures the time a system takes to return to balance after a perturbation. Since the years 1970, its definition has considerably changed. The one commonly admitted today is formulated by Holling (1973), who defines resilience as the ability of a system to integrate a perturbation in its working, without for (...)