2019 № 1(42)

Contents
  1. Sobiesevich A. L., Sobiesievich L.E. FORERUNNERS OF ENDOGENOUS CATASTROPHES //journal “Problems of informatics”. 2019, № 1. P. 4-29.
  2. Bredikhin S. V., Lyapunov V. M. Shcherbakova N. G. SPECTRAL ANALYSIS  OF THE JOURNAL CITATION NETWORK.  PART II //journal “Problems of informatics”. 2019, № 1. P. 30-41.
  3. Glinskiy B., Chernykh I., Martynov V., Sapetina A., Weins D. THE SIBERIAN SUPERCOMPUTER CENTER FOR COLLECTIVE USE AND ITS APPLICATION FOR THE CREATION OF COMPUTATIONAL TECHNOLOGIES.
  4. Narinyani A. S. INTRODUCTION TO SUBDEFINITION  

Sobiesevich A. L., Sobiesievich L.E

Schmidt Institute of Physics of the Earth, Russian Academy of Sciences (IPE RAS), 123242, Moscow, Russia

FORERUNNERS OF ENDOGENOUS CATASTROPHES   
 
UDK 550.385.3, 550.343
In the second half of the last century, geophysicists and seismologists has started to study the experimentally observed seismogravitational processes and accompanying induced anomalous (gravitomagnetic) perturbations in variations of the Earth's magnetic field. It gas been suggested that mentioned field structures contain useful information on the location and possibly the time of the forthcoming catastrophic earthquake.
The results of the first full-scale instrumental observations of a separate class of geophysical processes that reflect the conditions for the development of specific variations in the structure of geophysical fields of the Earth are considered. Initial work on this problem is directly related to the series of dedicated experiments at the SB RAS Bystrovsky geophysical test site, under the supervision of academician Anatoly Semenovich Alekseev. At that time A. S. Alekseev has worked on the theory of the “integral precursor” of earthquakes and has contributed into solving a separate class of fundamental problems related to the development of methods of active seismology, including the Earth's global tomography using controlled vibroseismic sources.
In the course of the experiments carried out at the Bystrovsky test site on the one-hundred-ton vibroseismic source, various geophysical fields induced in geospheres were studied. It has been shown for the first time in the practice of field observations the possibility to separate the specific class of gravitomagnetic disturbances induced in the lithosphere by powerful seismic sources.
Four years later, our scientific results were confirmed in the set of experiments carried out at the same test site by scientists of the SB RAS.
Further investigations of the class of seismogravitational processes and accompanying gravitomagnetic disturbances, which may be considered as short-term forerunners of powerful seismic events, were continued at the Geophysical observatory in Northern Caucasus.
Observations of variations in the Earth's magnetic field have confirmed that powerful seismic events are likely to be preceded by specific yet anomalous ULF gravitomagnetic disturbances that resemble signals generated by means of vibroseismic sources. It has been established that the seismogravitational processes identified in the Observatory and associated gravitomagnetic disturbances are an integral part of the induced geophysical fields that originate in the focal zones of the “forthcoming” seismic extents and are being studied today by geophysicists using the data of the “Intermagnet” global network. The observed variations may have been recommended as a potential medium-term to short-term precursors of disasters of endogenous nature.
Nowadays, geophysics has defined the fundamental physical fields that are used to describe the universe. Historically, among the fundamental physical fields responsible for the electromagnetic and the gravitational interaction were initially discovered. They are well studied in the framework of theoretical and experimental physics, opening up new horizons for knowledge of the world. An example of this is gravity waves, which have been successfully registered by LIGO detectors. The scientific discovery of a group of physicists from the United States, Russia and other countries, awarded the Nobel Prize, makes it necessary to take a fresh look at seismic and gravitational processes in the geospheres of the Earth related to the preparation and development of large endogenous catastrophes.
Instruments at the Geophysical Observatory in placeNorthern Caucasus constantly may allow us to determine the presence of seismogravitational interactions. These scientific data can become the fundamental basis that in the future will allow us to understand the deep nature of the seismogravity and associated induced gravitomagnetic disturbances in the lithosphere and other geospheres of the Earth. While analyzing the obtained scientific results, we always remember the good advice of the Academician A. S. Alekseev, who taught us to approach the analysis of complex wave structures generated by active dilatational restructuring in a real geophysical environment. It becomes clear that the experimental study of a specific class of fundamental problems we have identified in recent years related to the formation of long-period seismogravity processes and ULF gravitomagnetic disturbances in geospheres is becoming one of the defining problems of geophysics today.
Seismogravity processes and gravitomagnetic perturbations recorded at large distances from the focal region contain valuable scientific information about geophysical processes developing in focal structures before the main shock. To use such information in order to attempt a `forecast' of the expected place and time of the forthcoming seismic event, a network of observatories should be developed reflecting separate stages of focal structure formation, geophysical equipment should be improved, other well-known technologies should be used to make predictions of the development of large earthquakes.
Finishing a brief presentation of a number of new ideas and scientific results obtained, many of which were discussed at the initial stage with Anatoly Semenovich Alekseev, and we would like to note that the actual problems of active seismology and the tasks associated with the earthquake prediction were always in the scope of his scientific interests.
So at the end of January 2007, when he was already in sick, Anatoly Semenovich wrote to us: «Studying the fine structure of the structure of geometrical and material in homogeneities of the mantle and the core of the Earth becomes, apparently, not only a task of geotectonics. The drainage system of heat and mass transfer from the core to the surface layers may be of practical interest for the prediction of hydrocarbon provinces and local structures. The evolution of these inhomogeneities can be of fundamental importance for assessing the conditions for the emergence and evolution of the biosphere. For these reasons, the creation of the «Vibro-sounding of the mantle and core of the Earth» method, which is equivalent to the well-developed seismic method, becomes topical. A fundamentally new scientific and technical problem here is the creation of a precision-controlled, powerful (5-10 thousand tons) cheap and easily mounted, environmentally safe seismic vibrational source. The project of such a source is already being considered. In scientific and technical terms, it can be based on the principles developed in the successfully created method of vibration sounding of the earth's crust which has been used in country-regionRussia for more than two decades, and in recent years in placecountry-regionJapan. In this situation, I consider it is necessary to create the instruments and method for a detailed study of the mantle and core of the Earth, for which purpose it is feasible to fully utilize the experience of the Siberian Branch of RAS on the topics «Earth Vibrational Surveying» and «Active Seismology». Please let us know your comments and suggestions on the feasibility and reality of the organization of the project under discussion at the SB RAS. The Appendix (below) provides an overview of the scientific and practical aspects of Earth degassing. The study of gas-fluid dynamics drainage systems can be carried out within the framework of the mentioned «Earth Vibrational Sounding Project-2. Yours A. S. Alekseev».
The time will come, and the scientific background of Academician Anatoly Semenovich Alekseev will be even more in demand. The young generation of scientists will build powerful seismic vibrators and conduct controlled experiments that will allow a glimpse into the deep structures of the Earth's core, which is actively affecting other geospheres.
Key words: endogenous hazards and catastrophes, seismogravitational processes, active seismology, global vibroseismic sounding of the Earth.
 

 

Bibliographic reference: Sobiesevich A. L., Sobiesievich L.E. Forerunners of endogenous catastrophes   //journal “Problems of informatics”. 2019, № 1. P. 4-29. DOI: 10.24411/2073-0667-2019-00001

article

Bredikhin S. V., Lyapunov V. M., Shcherbakova N. G.

Institute of Computational Mathematics and Mathematical Geophysics SB RAS, 630090, Novosibirsk, Russia

SPECTRAL ANALYSIS  OF THE JOURNAL CITATION NETWORK.  PART II   

UDK 001.12+303.2

The cluster analysis of a finite set of data points allows to obtain its partitioning $C$ into uniform groups on the basis of similarity between points. The similarity relation between points form a basis for creation of a matrix of similarity A=(aij) where aij - a similarity measure. The matrix can be considered as the adjacency matrix of the weighed network, and the problem can be formulated as an optimizing problem of finding the minimum cut size of the graph that can be solved by methods of the spectral analysis and linear algebra. In most cases, depending on a formulation of the objective function, which formalizes the idea of grouping, eigenvectors of the Laplacian or adjacency matrix are investigated.

Algorithms of a spectral clustering can be divided into two types. The recursive method starts with a division of graph vertices into two subsets (bi-сlustering), with the subsequent application of the algorithm to induced subgraphs. The corresponding spectral problem is solved and then is found the partitioning of the components of the eigenvector (usually the second smallest eigenvector of a Laplacian matrix) into two sets containing nearly equal values. Herewith the data point i is projected onto the component i of the vector.

In case of k-way clustering the algorithm finds k  segments in one pass. It uses k  eigenvectors of the consistent matrix. Segments are extracted by finding the approximately equal components in selected vectors. For example, the data point i  is projected onto the tuple of components i  of vectors, the tuples can be regarded as points in  k-dimensional space or k-dimensional vectors and clustered by some known algorithm. It should be noted that the majority of the developed algorithms are designed for undirected graphs. To apply such algorithm to the directed graph, it must be transformed to undirected. Typical ways to obtain the symmetrical matrix A’ from the original adjacency matrix A include A'=A+AT, A'=AAT, A'=AAT.

This work follows Bredikhin, etc. (2017, 2018) that are focused on spectral clustering algorithms and their applicability to identify categories in the set of scientific journals. We build the citation network on the basis of the asymmetric relation R(i, j) between scientific journals i and j  which means that the aggregated journal i  contains at least one article which cites (contains a reference to) some article of the journal j. The problem of spectral clustering of graph in terms of the normalized cut is considered. The approach Meila, Pentney (2007) based on the minimization of the general weighed cut, WCut (), is used for partitioning of the directed graph. For comparison of the results of clustering of the original citation network and the undirected network obtained by transformation A'=A+AT  we implemented the algorithm based on minimization of the normalized cut MNCut() Shi, Malik (2000).

The implemented algorithms were applied to clustering of the citation network of the scholarly journals in the field of economics. We consider a group ``natural'' if the journals included relate to one or two scientific disciplines. We use Jel Classification System as a standard. The analysis of the results revealed their dependence on a number of factors: the used algorithm; either original directed graph is examined or transformed undirected graph; the way of symmetrization; is the strength of the relationship between data points taken in account (weighted /unweighted graph); the measure of the similarity of two partitions used (consistency index).

Key words: spectral clustering, normalized cut, generalized weighted cut, citation network.

Bibliographic reference: Bredikhin S. V., Lyapunov V. M., Shcherbakova N. G. Spectral analysis  of the journal citation network.  Part II   //journal “Problems of informatics”. 2019, № 1. P. 30-41. DOI: 10.24411/2073-0667-2019-00002

article

Glinskiy B., Chernykh I., Martynov V., Sapetina A., Weins D.

Institute of Computational Mathematics and Mathematical Geophysics SB RAS, 630090, Novosibirsk, Russia

THE SIBERIAN SUPERCOMPUTER CENTER FOR COLLECTIVE USE AND ITS APPLICATION FOR THE CREATION OF COMPUTATIONAL TECHNOLOGIES.

UDK}{681.32}

The paper describes the development of two directions of activity initiated by Academician A.S. Alekseev in  the ICMMG SB RAS: a supercomputer center for collective use and active seismology using powerful vibroseismic  sources. The main stages of the development of the Center for Collective Use  Siberian Supercomputer Center ICMMG SB RAS, its role in solving large problems of mathematical modeling in the Siberian Branch of the  Russian Academy of Sciences are presented.

Another direction is associated with the development of ideas for vibroseismic monitoring of seismic objects.

Mathematical modeling of living magmatic volcanoes monitoring problem has shown the principal possibility of prediction of catastrophic eruptions by the method of vibroseismic monitoring. Numerical simulation using multi-level supercomputer technology developed by the authors, including co-design, scalability of algorithms based on simulation, and an estimation of the energy efficiency of algorithms was performed.

Key words: center of collective use, numerical modeling, supercomputer technology, magmatic volcanoes, equations of the theory of elasticity, co-design, energy efficiency.

 

Bibliographic reference: Glinskiy B., Chernykh I., Martynov V., Sapetina A., Weins D. The Siberian Supercomputer Center for Collective Use and Its Application for the Creation of Computational Technologies. 2019, № 1. P. 42-60. DOI: 10.24411/2073-0667-2019-00003

article

Narinyani A. S.

Introduction to subdefinition

UDK 519.65: 519.85; 004.94; 004.82

Institute of Computational Mathematics and Mathematical Geophysics SB RAS, 630090, Novosibirsk, Russia

Subdefinite models (S-models) are a new theory and technology of efficient solution of a wide range of problems from applied calculations to processing knowledge and problems of artificial intelligence. S-models refers to the direction of constraint programming, actively developed the last time in the world, as one of the most promising in IT. S-models qualitatively extends the possibilities of working with information and computational models of increased complexity, allowing to significantly simplify the process of creating next-generation systems and technologies, in particular in such areas as economics, management, complex objects and production processes management, engineering calculations and many others. S-models allow you to actively interact with the entire solution space, which in principle exceed the capabilities of traditional algorithmic methods and provide a qualitative leap in solving key problems in the development of modern information technologies.

 

Key words: computational models, constraint programming, method of subdefinite models, artificial intelligence, knowledge representation, NE-factors.

 

 

Bibliographic reference: Narinyani A. S.Introduction to subdefinition  //journal “Problems of informatics”. 2019, № 1. P. 61-82. DOI: 10.24411/2073-0667-2019-00004

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