This paper addresses the problem of flocking motion in the context of port-Hamiltonian systems. The port-Hamiltonian framework offers advantages in modeling networks, dissipation, and heterogeneous agents. In this reg...
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Active metamaterials are engineered structures that possess novel properties that can be changed after the point of manufacture. Their novel properties arise predominantly from their physical structure, as opposed to ...
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Context. The study of stellar structure and evolution depends crucially on accurate stellar parameters. The photometry from space telescopes has provided superb data that allowed asteroseismic characterisation of thou...
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Context. The study of stellar structure and evolution depends crucially on accurate stellar parameters. The photometry from space telescopes has provided superb data that allowed asteroseismic characterisation of thousands of stars. However, typical targets of space telescopes are rather faint and complementary measurements are difficult to obtain. On the other hand, the brightest, otherwise well-studied stars, are lacking seismic characterization. Aims. Our goal is to use the granulation and/or oscillation time scales measured from photometric time series of bright red giants (1.6 ≤ V mag ≤ 5.3) observed with BRITE - Constellation to determine stellar surface gravities and masses. Methods. We use probabilistic methods to characterize the granulation and/or oscillation signal in the power density spectra and the autocorrelation function of the BRITE - Constellation time series. Results. We detect a clear granulation and/or oscillation signal in 23 red giant stars and extract the corresponding time scales from the power density spectra as well as the autocorrelation function of the BRITE - Constellation time series. To account for the recently discovered non-linearity of the classical seismic scaling relations, we use parameters from a large sample of Kepler stars to re-calibrate the scalings of the high- and low-frequency components of the granulation signal. We develop a method to identify which component is measured if only one granulation component is statistically significant in the data. We then use the new scalings to determine the surface gravity of our sample stars, finding them to be consistent with those determined from the autocorrelation signal of the time series. We further use radius estimates from the literature to determine the stellar masses of our sample stars from the measured surface gravities. We also define a statistical measure for the evolutionary stage of the stars. Conclusions. Our sample of stars covers low-mass stars on the lower giant br
To promote the information technology development of the enterprise, by means of wireless sensor network, the industrial monitoring system is designed and is suitable for industrial automation and process Automation n...
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ISBN:
(纸本)9781424479689
To promote the information technology development of the enterprise, by means of wireless sensor network, the industrial monitoring system is designed and is suitable for industrial automation and process Automation network. The hardware and the software of the system are mainly introduced, and the test results are given Industrial wireless sensor network technology is a new communication technology for information exchange between devices, and it will play an important role for improving product quality, reducing production costs and it is very suitable for used in harsh environments of industrial fields with anti-interference ability, low energy consumption, real-time characteristics.
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