Anomalous effects in a trapped Bose-Einstein condensate

Abstract

We study the anomalous density in an ultra-cold trapped bose gas in a variational framework, for both zero and finite temperature. We show that it is finite in 1D, while it is logarithmically and linearly divergent in 2D and 3D. The renormalization that we adopt is more reliable and compatible with the variational scheme. The main outcome is that the anomalous and non condensate densities are of the same order of magnitude and should therefore be treated on an equal footing.

Design and Research of Intelligent Knowledge Push Model

“…

In viewing of information overload environment,traditional search engine has inherent insufficiency about retrieval accuracy and query mode,together with the characteristics of decision tree algorithm and knowledge push,this paper presets an intelligent knowledge push model,and discuss the mechanism of this model.The model strive to improve the retrieval efficiency and realize the intelligent service.

IntroductionIn the network era, because of the information explosion that makes the increase the amount of information.How to query the information they want to that becomes more and more important in the vast cyber source, therefore there have specialized web search service web sites, such as Google, Baidu, Yahoo etc.. However, the information resource capacity will increase at an annual rate of nearly 80% [1][2] . Facing with digital information that grows with each passing day, on the one hand ,it need to increase the information resources storage capacity, making it easier for users to access to more information, but on the other hand,it is convenience for user in the enjoyment of massive digital resource,but at the same time,it also encountered the "information overload" problem.The user how to be more effective, more accurately find themselves interested in information and filtering that there are nothing to do with the information they need, truly "Each takes what he needs".

…”