AE signal extraction under the strong noise
According to the technology of using acoustic emission signal to extrapolate the acoustic emission source, the multiple signal classification algorithm based on far-field uniform linear array model had been researched in this paper. Combined with the property of AE monitoring, we present that the far-field multiple signal classification algorithm can be applied to estimate the position of the AE signal source. We can basically find the position of the AE signal source by making this algorithm adaptation with roadway shape and workface in the coal mine AE signal detection. The simulation results show that the proposed algorithm could effectively estimate the position of the AE signal source.
Estimation of the Site of Hypocenter and the Magnitude of Seism Based on Array Signal Processing
The first section of this paper presents a new approach to estimate the location and magnitude of seismic origin in the important area and the region suffered frequently from seism.The approach is mathematically analyzed in detail.The notable achieve-ments include the model of realistic lithosphere fabricated with complicated nonuniform transmission media and its shifted simplified al-ternative constructed with uniform transmission media.And then a concrete algorithm is detailed for clarity followed with the simulation results generated by computer.It is easy to find by the new approach people are probably free of the puzzle in locating the hypocenter for the special monitored area.
New records of Grania (Clitellata, Enchytraeidae) in the Northeast Atlantic (from Tromsø to the Canary Islands), with descriptions of seven new species
Previous northeast Atlantic records of Grania have been mainly from Germany, southern Scandinavia, and the Atlantic shores of France, Spain and Ireland. They were referred to eight species, with one, G. atlantica, reported from the continental slope. We have examined various unpublished collections from sources spanning from the Canary Islands to the Norwegian Arctic. Apart from new information on morphology, taxonomy, and distribution of known species, we describe seven new taxa (G. canaria, G. fortunata, G. mauretanica, G. aquitana, G. vikinga, G. torosa, and G. papillinasus). The collection of G. papillinasus from 2630-2885 m represents a new depth record for Enchytraeidae. Twenty-five of the now 57 Grania species occur in the North Atlantic. The North Atlantic drift moderates sea temperatures along the northeast Atlantic coasts, probably facilitating the wide latitudinal range of some taxa, as well as actual dispersal within the region. A "chaetal index" (chaetal length : chaetal foot length) is proposed to differentiate L-shaped chaetae at the species level. Complex relationships within the "type 6 group" of Grania suggest that groupings established using certain combinations of penial, chaetal and spermathecal patterns may not be monophyletic. For a better phylogenetic resolution, additional morphological details of these and other characters are needed.