lingling zhang

Data mining, an efficient method of business intelligence, is a process to extract knowledge from large scale data. As the augment of the size of enterprise and the data, data mining as a way to make use of the data become more and more necessary. But now most of the ...

The email has profoundly affected our ways of life. In the year 2001, many Web sites begin operating the charge emails in china. Recently the foreign Internet company serves free email with large storage capability, which threats the existence of charge email. The churn of email users is serious. This paper studied the churn of the customer using the way

Abstract The rapid development of data technology, as exemplified by data mining and Internet growth, creates a large information overload and forthcoming knowledge overload. Data mining discovers a large mount of knowledge, but not all of the knowledge is useful. ...

Association mining can generate large quantity of rules, most of which are not interesting to the user. Interestingness measures are used to find the truly interesting rules. This paper presents a review of the available literature on the various interestingness measures, which generally can be divided into two categories: objective measures based on the statistical strengths or properties of the discovered rules, and subjective measures which are derived from the userpsilas beliefs or expectations of their particular problem domain. We sum up twelve measure criteria which are concerned by many researchers and evaluate the strengths and weaknesses of the two categories of measures. At last, we pointed out that the combination of objective and subjective measures would be a possible research direction.

Aqueous suspensions containing 4.45 × 10−5 − 1.25 × 10−3 M ZnO particles exhibit a strong antibacterial activity against E. coli under the dark conditions. The dominant mechanisms of such antibacterial behaviour are found to be either or both of chemical interactions between hydrogen peroxide and membrane proteins, and chemical interactions between other unknown chemical species generated due to the presence of ZnO particles with the lipid bilayer. The effect of direct physical interactions between nanoparticles and biological cells are found to play a relatively small role under the conditions of this study.

The antibacterial behaviour of suspensions of zinc oxide nanoparticles (ZnO nanofluids) against E. Coli has been investigated. ZnO nanoparticles from two sources are used to formulate nanofluids. The effects of particle size, concentration and the use of dispersants on the antibacterial behaviour are examined. The results show that the ZnO nanofluids have bacteriostatic activity against E. coli. The antibacterial activity increases with increasing nanoparticle concentration and increases with decreasing particle size. Particle concentration is observed to be more important than particle size under the conditions of this work. The results also show that the use of two types of dispersants (Polyethylene Glycol (PEG) and Polyvinylpyrolidone (PVP)) does not affect much the antibacterial activity of ZnO nanofluids but enhances the stability of the suspensions. SEM analyses of the bacteria before and after treatment with ZnO nanofluids show that the presence of ZnO nanoparticles damages the membrane wall of the bacteria. Electrochemical measurements using a model DOPC monolayer suggest some direct interaction between ZnO nanoparticles and the bacteria membrane at high ZnO concentrations.