<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>13</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Miguel A. Gutiérrez-Naranjo</style></author><author><style face="normal" font="default" size="100%">Mario J. Pérez-Jiménez</style></author><author><style face="normal" font="default" size="100%">Agustín Riscos-Núñez</style></author></authors><secondary-authors><author><style face="normal" font="default" size="100%">Miguel A. Gutiérrez-Naranjo</style></author><author><style face="normal" font="default" size="100%">Gheorghe Paun</style></author><author><style face="normal" font="default" size="100%">Mario J. Pérez-Jiménez</style></author></secondary-authors></contributors><titles><title><style face="normal" font="default" size="100%">Multidimensional Sevilla Carpets associated with P systems</style></title><secondary-title><style face="normal" font="default" size="100%">Cellular Computing (Complexity Aspects)</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2005</style></year></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://www.cs.us.es/~marper/investigacion/esf-2.pdf</style></url></web-urls><related-urls><url><style face="normal" font="default" size="100%">http://cantor.cs.us.es/files/esf-2.pdf</style></url></related-urls></urls><publisher><style face="normal" font="default" size="100%">Fénix Editora</style></publisher><pub-location><style face="normal" font="default" size="100%">Sevilla, Spain</style></pub-location><pages><style face="normal" font="default" size="100%">225-235</style></pages><isbn><style face="normal" font="default" size="100%">84-609-5338-6 </style></isbn><abstract><style face="normal" font="default" size="100%">In this paper we address the problem of describing the complexity of the evolution of a P system. This is especially difficult in the case of P systems where the number of membranes increases along the computation, via division or creation of membranes. In these cases the number of steps of a computation is not sufficient to evaluate the complexity. Sevilla Carpets were introduced in [1], and they describe the space-time complexity of P systems. Based on them, we define a four-dimensional manifold which can be used to compare evolutions of P systems.</style></abstract></record></records></xml>