scholarly journals The generalized centrality method for analyzing network cyberspace

2019 ◽  
pp. 55-64
Author(s):  
Natalia Nikolaevna Gorlushkina ◽  
Sergei Evgenievich Ivanov ◽  
Lubov Nikolaevna Ivanova
Keyword(s):  
Mathematical Model ◽  
Social Networks ◽  
Information Dissemination ◽  
Relative Weight ◽  
Graph Model ◽  
Graph Models ◽  
Number Of Factors ◽  
The Subject ◽  
Comparison Of The Results ◽  
Centrality Analysis

The subject of the research is the methods of network cyberspace analysis based on graph models. The analysis allows to find leaders of groups and communities, to find cohesive groups and visualize the results. The main methods of the graph theory used for cyberspace social networks are the methods of analyzing the centrality to determine the relative weight or importance of the vertices of the graph. There are known methods for analyzing centralities: by degree, by proximity, by mediation, by radiality, by eccentricity, by status, eigenvector, referential ranking. The disadvantage of these methods is that they are based only on one or several properties of the network participant. Based on the centrality analysis methods, a new generalized centrality method is proposed, taking into account such participant properties as the participant's popularity, the importance and speed of information dissemination in the cyberspace network. A mathematical model of a new method of generalized centrality has been developed. Comparison of the results of the presented method with the methods of the analysis of centralities is performed. As a visual example, a subgroup of cyberspace consisting of twenty participants, represented by a graph model, is analyzed. Comparative analysis showed the accuracy of the method of generalized centrality, taking into account at once a number of factors and properties of the network participant.

scholarly journals GEORGE KEITH BATCHELOR 8 March 1920–30 March 2000 Founding Editor, Journal of Fluid Mechanics, 1956

2000 ◽  
Vol 421 ◽  
pp. 1-14 ◽  
Author(s):  
HERBERT E. HUPPERT
Keyword(s):  
Fluid Mechanics ◽  
International Organizations ◽  
Solid Mechanics ◽  
Applied Mathematics ◽  
Fluid Flows ◽  
Theoretical Physics ◽  
Founding Editor ◽  
Number Of Factors ◽  
Quantitative Understanding ◽  
The Subject

George Batchelor was one of the giants of fluid mechanics in the second half of the twentieth century. He had a passion for physical and quantitative understanding of fluid flows and a single-minded determination that fluid mechanics should be pursued as a subject in its own right. He once wrote that he ‘spent a lifetime happily within its boundaries’. Six feet tall, thin and youthful in appearance, George's unchanging attire and demeanour contrasted with his ever-evolving scientific insights and contributions. His strongly held and carefully articulated opinions, coupled with his forthright objectivity, shone through everything he undertook.George's pervasive influence sprang from a number of factors. First, he conducted imaginative, ground-breaking research, which was always based on clear physical thinking. Second, he founded a school of fluid mechanics, inspired by his mentor G. I. Taylor, that became part of the world renowned Department of Applied Mathematics and Theoretical Physics (DAMTP) of which he was the Head from its inception in 1959 until he retired from his Professorship in 1983. Third, he established this Journal in 1956 and actively oversaw all its activities for more than forty years, until he relinquished his editorship at the end of 1998. Fourth, he wrote the monumental textbook An Introduction to Fluid Dynamics, which first appeared in 1967, has been translated into four languages and has been relaunched this year, the year of his death. This book, which describes the fundamentals of the subject and discusses many applications, has been closely studied and frequently cited by generations of students and research workers. It has already sold over 45 000 copies. And fifth, but not finally, he helped initiate a number of international organizations (often European), such as the European Mechanics Committee (now Society) and the biennial Polish Fluid Mechanics Meetings, and contributed extensively to the running of IUTAM, the International Union of Theoretical and Applied Mechanics. The aim of all of these associations is to foster fluid (and to some extent solid) mechanics and to encourage the development of the subject.

The interpretation of unsolvable λ-terms in models of untyped λ-calculus

1998 ◽  
Vol 63 (4) ◽  
pp. 1529-1548 ◽  
Author(s):  
Rainer Kerth
Keyword(s):  
Graph Model ◽  
Stable Model ◽  
Graph Models ◽  
Stable Models

AbstractOur goal in this paper is to analyze the interpretation of arbitrary unsolvable λ-terms in a given model of λ-calculus. We focus on graph models and (a special type of) stable models. We introduce the syntactical notion of a decoration and the semantical notion of a critical sequence. We conjecture that any unsolvable term β-reduces to a term admitting a decoration. The main result of this paper concerns the interconnection between those two notions: given a graph model or stable model , we show that any unsolvable term admitting a decoration and having a non-empty interpretation in generates a critical sequence in the model.In the last section, we examine three classical graph models, namely the model of Plotkin and Scott, Engeler's model and Park's model . We show that and do not contain critical sequences whereas does.

Communication in social networks of St. Petersburg as a means of adaptation of ethnocultural communities

Litera ◽  
2021 ◽  
pp. 38-55
Author(s):  
Rivaa Mukhammad Salem Alsalibi
Keyword(s):  
Social Networks ◽  
Social Media ◽  
Ethnic Communities ◽  
Sense Of Security ◽  
The Social ◽  
The Subject ◽  
Development Prospects

The subject of this research is the specifics, forms and functions of interaction in social media groups between the representatives of ethnic communities. The goal consists in determination of the role of social networks in adaptation of ethnocultural communities of St. Petersburg. The research is based on the polling technique for acquisition of information on the cognitive, emotional, and behavioral state of a person. The survey was conducted via distribution of questionnaires among the representatives of ethnic groups. The article also employs the method of systematic scientific observation over the social media groups, topic raised therein, as well as reading and analysis of the comments. The scientific novelty of this work consists in outlining of the nature, trends and development prospects of cross-cultural communications as the channel for ethnocultural interaction.  The main conclusions, which touch upon users from various ethnic communities who do not have enough experience in organization of activity of social media groups, demonstrate that it causes the loss of the sense of security, accumulation of prejudices and escalation of interethnic conflicts, as well as preference of the with restricted access, which contributes to lock down of the group and impedes adaptation in the accepting society. Stabilization of situation can be achieved by improvement of the quality of content posted in the social media, as well as level of their administration.

MATHEMATICAL MODEL AND EXPERIMENTAL ESTIMATION OF THERMAL PROCESSES IN HEATING MODULE AS A PART OF STEAM ABLATION DEVICE FOR VARICOSE VEINS TREATMENT

2021 ◽  
pp. 117-125
Author(s):  
Дина Владимировна Кривоносова ◽  
Евгений Сергеевич Ермолаев
Keyword(s):  
Mathematical Model ◽  
Varicose Veins ◽  
Thermal Power ◽  
Thermal Characteristics ◽  
Steam Injection ◽  
Heating Element ◽  
Vein Wall ◽  
Tissue Heating ◽  
Comparison Of The Results ◽  
The Mathematical Model

На сегодняшний день в России для лечения варикозного расширения вен часто проводятся малоинвазивные операции методами радиочастотной или лазерной облитерации, при этом метод паровой облитерации при лечении варикозной болезни не применяется совсем. Однако метод паровой облитерации обладает существенными преимуществами: малый объём и биоинертность рабочей среды - водяного пара, его невысокая температура - 120 °С, исключающая вероятность образования нагара и перфорации венозной стенки. Целью данной работы является разработка математической модели для расчёта тепловых характеристик блока нагревания, входящего в устройство для лечения варикозной болезни методом паровой облитерации. Модель описывает теплообменные процессы в гидравлической трубке блока нагревания и может быть полезна при расчёте размеров нагревательного элемента, обеспечивающих нагрев и парообразование определённой порции воды. С целью верификации математической модели результаты моделирования были сопоставлены с экспериментальными данными. Была проведена серия экспериментов, в ходе которых были получены значения энергии, содержащейся в одной инжекции пара, и объём воды в одной инжекции, а также оценена фактическая тепловая мощность нагревателя. Сравнение результатов имитационного моделирования и значения фактической тепловой мощности пара, полученной экспериментальным путем, показала работоспособность математической модели. Разработанная математическая модель позволяет подбирать геометрические параметры нагревательного элемента в зависимости от требуемой тепловой мощности, которая должна быть обеспечена блоком нагревания, а также варьировать параметры нагревательного элемента для разной степени нагрева тканей Today in Russia minimally invasive varicose veins treatment is often performed using radiofrequency or laser ablation, while the method of steam ablation is not used at all. However, the steam ablation method has significant advantages: a small volume and biological inertness of the working substance - sterile water vapor, its low temperature - 120 °C, excluding the carbon deposits and perforation of the vein wall. The purpose of this work is to develop a mathematical model for calculating the thermal characteristics of the heating module as a part of the device for varicose veins treatment using steam ablation. The model describes heat exchange processes in the hydraulic circuit of the heating module and can be applied to calculate the dimensions of the heating module which provides heating and vaporization of a certain portion of water. In order to verify the mathematical model, the simulation results were compared with experimental data. A series of experiments were carried out in which the energy contained in one steam injection and the volume of water in one injection were estimated, as well as the actual thermal power of the heating module. Comparison of the results of simulation and the value of the actual thermal power of steam obtained experimentally showed the efficiency of the mathematical model. The proposed mathematical model allows to select the geometric parameters of the heating element depending on the required thermal power, which must be provided by the heating module, and also to vary the parameters of the heating element for different degrees of tissue heating

Conducting Psychological Examinations for Citizens in Possession of Weapons: Strengthening State Control Over Circulation of Weapons

2021 ◽  
Vol 8 (2) ◽  
pp. 87-94
Author(s):  
Sergey N. Bokov ◽  
Maxim I. Zhdanov
Keyword(s):  
Social Networks ◽  
Specific Form ◽  
Personality Questionnaire ◽  
State Control ◽  
Gun Ownership ◽  
Frustration Tolerance ◽  
Psychological Analysis ◽  
Psychological Examination ◽  
The Subject ◽  
Analysis Of Social Networks

In the article, in connection with the introduction of amendments to the federal legislation, specific issues regarding the conducting of a psychological survey of citizens gun owners and candidates for gun ownership are considered. A battery of psychodiagnostic techniques that can be used in the course of a psychological examination (progressive matrices of J. Raven, a questionnaire of the Level of subjective control, and a method for diagnosing frustration tolerance from Rosenzweig, Minnesota Multidisciplinary Personality Questionnaire) is proposed and justified, as is an algorithm for conducting psychodiagnostic research. Furthermore, a proposal to include in the psychological examination, a psychological analysis of social networks (provided that the subject is a member of their group) has been made. The possible participation in the psychological survey gun owners and candidates for gun ownership psychologists of Rosgvardiya are justified and the specific form of their participation in the survey is indicated.

THE HEAP PARTS MOVEMENT ON THE SHAREBOARD SURFACE OF THE POTATO HARVESTING MACHINE

2021 ◽  
Vol 14(63) (1) ◽  
pp. 127-140
Author(s):  
Serhii HRUSHETSKYI ◽  
Vitaly YAROPUD ◽  
Ihor KUPCHUK ◽  
Ruslana SEMENYSHENA
Keyword(s):  
Mathematical Model ◽  
Experimental Studies ◽  
Separation Process ◽  
Kinematic Parameters ◽  
Quality Performance ◽  
Machine Operation ◽  
Degree Of Damage ◽  
Total Capacity ◽  
Comparison Of The Results

The article is devoted to the problem of the reduction of tubers mechanical damages while providing qualitative indicators of the potato heap separation process. Theoretical and experimental dependences of the influence of design and kinematic parameters of the machine operation on the quality performance are obtained. Within the field of experimental studies, a field installation was made to investigate the potato harvester as a whole on the efficiency of separation, the degree of damage, the magnitude of losses and the total capacity for aggregation. Comparison of the results of theoretical and experimental studies showed that the developed mathematical model of the process of separation of potato heap is adequate.

The clustering methods in graph models of social networks

2017 ◽  
Vol 11 ◽  
pp. 1007-1017 ◽  
Author(s):  
Tatiana Victorovna Zudilova ◽  
Sergei Evgenievich Ivanov
Keyword(s):  
Social Networks ◽  
Clustering Methods ◽  
Graph Models
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