Human Emergency Behaviour Characteristics in Large-scale Emergencies Based on Mobile Communication Data

The characteristics of human emergency behaviour under the emergency are a crucial scientific issue in basic emergency management research. The analysis of time dynamic aspects of human behaviour based on electronic footprint data provides a new method for quantitative investigation of this problem. Previous studies generally assumed that human behaviours were randomly distributed in time, but few studies studied the impact of emergencies and carried out prediction methods through social media data. Using mobile QQ space communication data, this paper from four kinds of emergencies and one kind of conventional event data, digging out the statistical characteristic on the time dimension of human communication behaviour, and in case of any emergencies, such as public security mode of evolution, to explore intrinsic emergency regularity of the impact of human communication behaviour model and further predict human behaviour characteristics. We found that the communication peaks accompanying an emergency are local in time, resulting in a communication avalanche that importantly engages eyewitness social networks. In mobile QQ space communication, the probability distribution of the interval time of the Posting behaviour sequence shows the statistical characteristics of power-law and approximate exponential tail. Compared with most of the typical Posting behaviour, the probability distribution of the interval time of the Posting behaviour sequence is higher. At the same time, the mnemonic is lower than most of the typical Posting behaviour, with a weak anti- mnemonic. These results are theoretically helpful in understanding the regularity of the impact of emergencies on human communication behaviour patterns and have potential application value in predicting the impact degree of crises and the analysis and classification of human social attributes.

Blind Adaptive Equalization for Aerospace Communication Channels

In some communication systems, it is desirable for the receiver to synchronize to the received signal and to adjust the equalizer without having knowledge of a training sequence. Blind equalization uses the initial adjustment of the coefficients without making use of a training sequence. Different adaptive blind equalization algorithms have been developed over the past four decades. In this paper, we investigate the effect of blind equalization on space communication channels. The space channel under investigation is considered to be a multipath frequency selective channel having four paths. The channel is subjected to the phenomenon of InterSymbol Interference (ISI) which severely degrades the performance of the space communication system. Two blind algorithms are used in equalizer adjustment. The impulse responses of the space channel, the blind equalizer and the combination of channel and equalizer for QPSK and 16-QAM transmission are shown. The scatter diagrams for the transmitted sequence, received sequence, and the output of the equalizer using two of the blind algorithms are shown.

Promising technologies for improving the efficiency of specialized aviation and rocket-space communication systems

Развитие авиационных и ракетно-космических систем специальной связи в настоящий момент характеризуется увеличением объемов речевых информационных сообщений. Речь, как наиболее привычная форма общения, позволяет выражать эмоции и личные качества говорящего, чего гораздо сложнее добиться иными путями информационного обмена. Растущий спрос на голосовую связь порождает необходимость выработки перспективных технологий повышения эффективности функционирования таких систем, анализ которых и проведен в данной статье. The development of aviation and rocket-space systems of special communication is currently characterized by an increase in the volume of speech information messages. Speech, as the most familiar form of communication, allows you to express the emotions and personal qualities of the speaker, which is much more difficult to achieve in other ways of information exchange. The growing demand for voice communication creates the need to develop promising technologies to improve the efficiency of such systems, the analysis of which is carried out in this article.