Patterns of creation and usage of wikipedia content

This is the Post-print version of the Article. The official Published version can be accessed from the link below - Copyright @ 2012 IEEEWikipedia is the largest online service storing user-generated content. Its pages are open to anyone for addition, deletion and modifications, and the effort of contributors is recorded and can be tracked in time. Although potentially the Wikipedia web content could exhibit unbounded growth, it is still not clear whether the effort of developers and the output generated are actually following patterns of continuous growth. It is also not clear how the users access such content, and if recurring patterns of usage are detectable showing how the Wikipedia content typically is viewed by interested readers. Using the category of Wikipedia as macro-agglomerates, this study reveals that Wikipedia categories face a decreasing growth trend over time, after an initial, exponential phase of development. On the other hand the study demonstrates that the number of views to the pages within the categories follow a linear, unbounded growth. The link between software usefulness and the need for software maintenance over time has been established by Lehman and other; the link betweenWikipedia usage and changes to the content, unlike software, appear to follow a two-phase evolution of production followed by consumption.This study is partly funded by the University of East London

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A manifestly covariant treatment of the free quantum eletromagnetic field, in a linear covariant gauge, is implemented employing the Schwinger's Variational Principle and the B-field formalism. It is also discussed the abelian Proca's model as an example of a system without constraints.Comment: 8 pages. Format PTPtex. No figur

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Alguns aspectos econômicos da cultura do cajueiro no Piauí.

Producao de castanha de caju no Piaui; Estrutura fundiaria das principais regioes produtoras; Alternativas para recuperacao e expansao da cajucultura piauiense; Medidas de curto prazo, medio prazo, longo prazo.bitstream/item/33979/1/Dc-006.pd

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