Intelligent Seismic-Acoustic System for Identifying the Location of the Areas of an Expected Earthquake

A brief overview of the state-of-the-art in the field of earthquake study and forecasting is presented in this paper. We analyze the principles of the methods of determining the coordinates of earthquake focuses by means of ground seismic stations. We demonstrate that those methods cannot be used in the system for monitoring of the beginning of the earthquake preparation process (in the network of RNM ASP stations). As we know, the earthquake preparation process is accompanied by spreading noisy seismic-acoustic signals. Theoretically, the system for monitoring of the beginning of the earthquake preparation process is based on the technologies for seismic-acoustic signal processing-Robust Noise Monitoring (RNM). Noise characteristics determined by RNM technologies indicate the beginning of anomalous seismic processes (ASP) and, consequently, the possibility of ASP monitoring. Considering that the seismic-acoustic signal can be represented as the sum of the useful signal and noise, we present the technologies for determining noise characteristics. It is demonstrated in the paper that a change in the estimate of the cross-correlation function between the useful signal and the noise, noise variance and the value of noise correlation determine the beginning of ASP. One RNM ASP station determines the beginning of ASP within a radius of about 500 km. Determining the location of an expected earthquake requires a network of RNM ASP stations. We analyze the results of noise technology-based monitoring of anomalous seismic processes performed from July 2010 to June 2015 on nine seismic-acoustic stations built at the head of 10 m, 200 m, 300 m and 1400 - 5000 m deep wells. Based on the results of the experimental data obtained in the period covering over three years, an intelligent system has been built, which allows for identifying the location of the zone of an earthquake, using the combinations of time of change in the estimate of the correlation function between the useful signal and the noise of the seismic-acoustic information received from different stations 10 - 20 hours before the earthquake. In the long term, the system can be used by seismologists as a tool for determining the location of the zone of an expected earthquake.

Robust Solutions to Uncertain Linear Complementarity Problems

In this paper, we adopt the robust optimization method to consider linear complementarity problems in which the data is not specified exactly or is uncertain, and it is only known to belong to a prescribed uncertainty set. We propose the notion of the p-robust counterpart and the p-robust solution of uncertain linear complementarity problems. We discuss uncertain linear complementarity problems with three different uncertainty sets, respectively, including an unknown-but-bounded uncertainty set, an ellipsoidal uncertainty set and an intersection-of-ellipsoids uncertainty set, and present some sufficient and necessary （or sufficient） conditions which p-robust solutions satisfy. Some special eases are investigated in this paper.