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.
Study on Threshold Detection of Micro-Seismic Signal Based on Constraint Judgment
Double threshold detection based on constraint judgment is proposed for micro-seismic signal detection. The improvement effect on Probability of False Alarm and influence on Probability of Detection are quantitatively analyzed with constraint judgment. The mathematical models of total PFA and PD of double threshold detection based on constraint judgment are built, and the validity of the mathematical model is verified by simulation tests and experiments. The results show that the signal-to-noise ratio under scheduled PFA and PD Call be decreased by introducing constraint judgment to double threshold detection, and improve the identification accuracy of micro-seismic signal.
Morphological characterization of Eustrongylides sp. larvae (Nematoda, Dioctophymatoidea) parasite of Rhinella marina (Amphibia: Bufonidae) from Eastern Amazonia.
Absctract Eustrongylides spp. nematodes have birds as final hosts and uses other vertebrates as intermediate/paratenic host (fish, amphibians and reptiles) and have zoonotic potential. In amphibians, the larvae may be located in the subcutaneous tissues, liver and mesentery, between the muscle fibres, especially in the lower limbs. Rhinella marina, which is widely observed in Brazil, has exhibited complex diversity in its helminth fauna, reflecting the unique habitat of the Amazon biome. For the first time, this study describes the morphological aspects of third-stage larvae of Eustrongylides sp. in Rhinella marina from Santa Cruz do Ararí, Marajó Archipelago, Eastern Amazonia, using light and scanning electron microscopy.