The limit set of a celullar automaton consists all the configurations that can appear after arbitrarily long computations. It is known never empty—it contains at least one homogeneous configuration. A CA called nilpotent if its just present work proves it algorithmically undecidable whether given one-dimensional cellular nilpotent. proof based on generalization well-known result about undecidability tiling problem plane. states remains even considers only so-called NW-deterministic tile...

Abstract There is no algorithm which will take a description of celluar automaton and determine whether it has zero topological entropy, or for any fixed ε > 0 compute its entropy to tolerance e. Furthermore set aperiodic Wang tiles arising from Penrose's kite dart used demonstrate specific examples cellular automata with single periodic point but non-trivial non-wandering sets, furthermore can be constructed have arbitrarily high entropy.

Abstract The article discusses lower and higher contexts for information phenomena, argues that there is clearly a need more concerted research effort in the latter sphere. discipline of science has traditionally favored contexts—like everyday life problem solving—that are neutral or even negative by nature. In contrast, neglected things pleasurable profound experiences, activities transcend daily grind. A literature sample scarce related to indicates beyond spotlight mainstream research,...

Purpose The purpose of this paper is to specify user‐defined relevance criteria by which people select hyperlinks and pages in web searching. Design/methodology/approach A quantitative qualitative analysis was undertaken talking aloud data from nine searches conducted about self‐generated topics. Findings Altogether 18 different for selecting were found. selection constituted, two, intertwined processes: the judgment hyperlinks, criteria, decision‐making concerning acceptance or rejection...

This paper discusses everyday life information seeking via the World Wide Web, and its many contexts at various levels of abstraction. First, empirical Internet-searching studies are reviewed, conclusion which is fact that they yield an exceedingly limited fragmentary picture context activity. Therefore, aim theoretical: to propose – based on holistic reflection earlier literature a truly contextual model Web searching from individual's perspective. The layers life-worlds, domains,...

Based on the interviews of 18 people in Finland 2001-2, conceptions Internet as an information source were explored. In general, reflect acceptability, accessibility and usability sources. Most appeared to be quite impressionistic, reflecting basic difficulty describing constantly changing nature Internet. Two major kinds identified. First, metaphorical conceptions, was primarily conceived terms space or place, for example, a library bazaar. Second, based actual use experiences significantly...