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In future optical transport networks, light-path performance analysis is of great practical significance for fully automated management. In general, the quality of transmission (QoT) of lightpaths, measured by optical quality factor or optical signal-to-noise ratio, has a complex time-varying process, along with the interactions of the other lightpath state parameters (LSPs), such as transmit power, chromatic dispersion, polarization mode dispersion. Current studies are mostly focused on lightpath QoT estimation, but ignoring lightpath-level data analytics. In this case, our article proposes a novel lightpath performance analysis method considering recurrence plot (RP) and cross recurrence plot (CRP). Firstly, we give a detailed interpretation on the recurrence patterns of LSPs via a qualitative 2-D RP representation and its quantitative measure. It can potentially enable the accurate and fast lightpath failure detection with a low computational burden. On the other hand, CRP is devoted to modeling the relationships between lightpath QoT and LSPs, and the correlation degree is determined by a geometric mean of multiple indexes of cross recurrence quantification analysis. From the view of application, such CRP analysis can provide the effective knowledge sharing to guarantee more credible QoT prediction. Extensive experiments on a real-world optical network dataset have clearly demonstrated the effectiveness of our proposal.

This paper discusses a multi-agent and its speech act theory supporting cooperative mechanical CAD. The multi-agent is constructed with organizer, agents and communication manager. The structures of the organizer and agent are elaborated. The communication manager consists of central management and dialog management. This speech act theory supports the agents communication involving more than 2 people. The Pr/T net of speech act and firing rules are presented. The multi-agent model has been put into practice of computer integrated autobody development, and make the distributed cooperative autobody design system more flexible and coordinate.

A technique of cross-correlation for the determination of stellar positions is proposed. It is a technique suitable for the recording of stellar positions on transit instruments, photoelectric astrolabes, and also on the meridian circles with reversed observing method. An advantage of this process is that there is no hypothesis required for the modelling image profile, and for the noise. It is closer to unbiased estimation. Results by this new method on a transit instrument are presented. For the brighter stars, there is no great difference in accuracy between the median position and the cross-correlation value according to the results.