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The amount of information contained in the typical Automatic Dependent Surveillance-Broadcast (ADS-B) terrestrial station system is often small，and it does not support the real-time collection of the flight target track data packets, the dynamic display of track information at the data level, and the more granularity of the historical playback of raw data packets. For these practical application needs，this article aims to build a set of ADS-B data packet collection and analysis system, and try to optimize the processing applications of the acquired messages after processing the host by the ADS-B ground station，designing the data collection method of ADS-B Category(Cat) 021 packet, using UDP multicast to connect externally to Cat 021 packet parsing module. According to the standard Cat 021 data packet protocol format, a corresponding message parsing algorithm is designed and implemented to parse and store the collected data messages in real time.

When radar receivers adopt digital channelization, it is prone to generating a cross-channel split signal, the rabbit ear effect, and a transition band repeated signal, leading to errors in radar signal sorting or identification. The pulse-splitting model and detection method proposed in this paper can model split pulses and identify them in radar pulse streams, facilitating the merging of split pulses to enhance sorting and identification performance. Firstly, the mechanism of splitting pulse generation is deeply analyzed, and the splitting site theory is proposed. Then, the split pulse signal model and the split pulse number statistical model based on geometric distribution are constructed, which are used to guide the construction of simulation data of split pulse flow with different characteristics. Furthermore, a time-domain convergence degree (TCD) index is proposed to characterize the pulse split phenomenon. At the same time, in order to avoid a large number of threshold searching problems in pulse-splitting detection, an empirical formula for the pulse-splitting detection threshold based on the TCD is given to quickly determine whether there is a pulse train split problem. The selected measured radar pulse stream is verified to follow a geometric distribution at a significance level of 0.05. The proposed method achieved a detection accuracy of at least 99.55% on the simulation dataset and at least 95.68% on the experimental dataset, validating the rationality of pulse-splitting modeling and the effectiveness of the detection method. [ABSTRACT FROM AUTHOR]

Pathological observations show that cancer cells frequently invade the surrounding normal tissue in collective rather than individual cell migration. However, general principles governing collective cell migration remain to be discovered. Different from individual cell migration, we demonstrated that the Notch‐1‐activation reduced collective cells speed and distances. In particular, Notch‐1‐activation induced cellular cytoskeletal remodelling, strengthened the intercellular junctions and cell‐matrix adhesions. Mechanistically, Notch‐1 activation prevented the phosphorylation of GSK‐3β and the translocation of cytoplasmic free β‐catenin to the nucleus, which increased E‐cadherin expression and tight intercellular junctions. Moreover, Notch‐1 signalling also activated the RhoA/ROCK pathway, promoting reorganization of F‐actin and contractile forces produced by myosin. Further, Notch‐1 activation increased cell adhesion to the extracellular substrate, which inhibited collective cell migration. These findings highlight that cell adhesions and cell–cell junctions contribute to collective cell migration and provide new insights into mechanisms of the modulation of Notch‐1 signalling pathway on cancer cell malignancy. [ABSTRACT FROM AUTHOR]

The weighted spectral distribution (WSD) is a metric defined on the normalized Laplacian spectrum. In this study, synchronic random graphs are first used to rigorously analyze the metric's scaling feature, which indicates that the metric grows sublinearly as the network size increases, and the metric's scaling feature is demonstrated to be common in networks with Gaussian, exponential, and power-law degree distributions. Furthermore, a deterministic model of diachronic graphs is developed to illustrate the correlation between the slope coefficient of the metric's asymptotic line and the average path length, and the similarities and differences between synchronic and diachronic random graphs are investigated to better understand the correlation. Finally, numerical analysis is presented based on simulated and real-world data of evolving networks, which shows that the ratio of the WSD to the network size is a good indicator of the average path length.