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Abstract: The method based on data fusion fault diagnosis is put forward and the two-step fusion diagnosis model of neural network and D-S evidence theory is given against the complexity and multiplicity when the fault of control system happens; the fault detection laboratory platform is erected based on the data fusion through the analysis of the electric actuator''s principle and typical faults, and on this basis, the fault of the electric actuator is diagnosed by the experiment and computer simulation. This method overcomes the uncertainty of the neural network fault diagnosis and improves the accuracy of system diagnosis, and the experiment result verified the method''s validity. [Copyright &y& Elsevier]

Abstract: The abundance of aerobic anoxygenic phototrophic bacteria (AAPB), a new functional group that plays important roles in marine carbon cycling, is determined frequently by infrared epifluorescence microscopic analysis (IREM) or high-performance liquid chromatography (HPLC) based on detecting BChl a (bacteriochlorophyll a) fluorescence signal at 880 nm. Unfortunately, the fluorescence signal is often influenced by environmental variables and physiological state of cell. Here we developed a real-time quantitative PCR (qPCR) assay based on pufM gene to specifically quantify AAPB in marine environments. High specificity and sensitivity for estimation of AAPB abundance were revealed by analysis of amplification products, melting curves and target sequences. The phylogenetic tree indicated that this primer set is suitable for a wide genetic diversity of AAPB, including α-3, α-4 Proteobacteria and clones of unclear taxonomic position. In contrast, no amplicon was obtained from green non-sulphur bacteria and oxygenic phototrophic bacteria such as Cyanobacterial genomic DNA. The melting behavior could indicate predominant phenotypes in AAPB community in addition to validating the products of qPCR. The AAPB was estimated to range from 1.3×104 cell/ml to 3.4×105 cell/ml in our 10 tested water samples by this qPCR assay. Further investigations on the abundance distribution of AAPB in marine environments using the qPCR assay may provide new insight into their ecological functions. [Copyright &y& Elsevier]