Integrable deformations, bi-Hamiltonian structures and nonintegrability of a generalized Rikitake system

2019 ◽  
Vol 16 (04) ◽  
pp. 1950059 ◽  
Author(s):  
Kaiyin Huang ◽  
Shaoyun Shi ◽  
Zhiguo Xu
Keyword(s):  
Galois Groups ◽  
Point Of View ◽  
Integrable Case ◽  
Analytic First Integrals ◽  
Rikitake System ◽  
Constants Of Motion ◽  
Integrable Deformations ◽  
Particular Solution ◽  
Almost All ◽  
Parameter Values

The aim of this paper is to investigate a generalized Rikitake system from the integrability point of view. For the integrable case, we derive a family of integrable deformations of the generalized Rikitake system by altering its constants of motion, and give two classes of Hamilton–Poisson structures which implies these integrable deformations, including the generalized Rikitake system, are bi-Hamiltonian and have infinitely many Hamilton–Poisson realizations. By analyzing properties of the differential Galois groups of normal variational equations (NVEs) along certain particular solution, we show that the generalized Rikitake system is not rationally integrable in an extended Liouville sense for almost all parameter values, which is in accord with the fact that this system admits chaotic behaviors for a large range of its parameters. The non-existence of analytic first integrals are also discussed.

scholarly journals Hamilton-Poisson Realizations of the Integrable Deformations of the Rikitake System

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Cristian Lăzureanu
Keyword(s):  
Periodic Orbits ◽  
Equilibrium Points ◽  
Integrable Case ◽  
Rikitake System ◽  
Integrable Deformations ◽  
The Stability

Integrable deformations of an integrable case of the Rikitake system are constructed by modifying its constants of motions. Hamilton-Poisson realizations of these integrable deformations are given. Considering two concrete deformation functions, a Hamilton-Poisson approach of the obtained system is presented. More precisely, the stability of the equilibrium points and the existence of the periodic orbits are proved. Furthermore, the image of the energy-Casimir mapping is determined and its connections with the dynamical elements of the considered system are pointed out.

scholarly journals How ethical challenges of covert observations can be met in practice

2021 ◽  
pp. 174701612110082
Author(s):  
Nicole Podschuweit
Keyword(s):  
Social Research ◽  
Role Playing ◽  
Great Distance ◽  
Point Of View ◽  
Ethical Challenges ◽  
Research Subjects ◽  
Written Information ◽  
Ethical Debate ◽  
The People ◽  
Almost All

This paper aims to bring into the ethical debate on covert research two aspects that are neglected to date: the perspective of the research subjects and the special responsibility of investigators towards their observers. Both aspects are falling behind, especially in quantitative social research. From a methodological point of view, quantitative forms of covert observation involve a great distance between the researcher and the research subjects. When human observers are involved, the focus is usually on the reliable application of the measuring instrument. Therefore, herein, a quantitative study is used as an example to show how the protection needs of both the observed persons and the observers can be met in practice. The study involved 40 student observers who covertly captured everyday conversations in real-world settings (e.g. in cafés or trains) by a highly standardised observation scheme. The study suggests that the anonymity of the research subjects and their trust in the observers are crucial for their subsequent consent. However, many participants showed only little or even no interest in the written information they were provided. Further, this study strongly emphasises how mentally stressful covert observations are to the observers. Almost all observers were worried in advance that the people they were observing would prematurely blow their cover and confront them. Role-playing and in-depth discussions in teams are good strategies to alleviate such and other fears and to prepare student assistants well for their demanding work in the field.

Bernhard Riemann’s legacy of 1859

2009 ◽  
Vol 93 (528) ◽  
pp. 468-475
Author(s):  
Graham Hoare
Keyword(s):  
Number Theory ◽  
Mathematical Physics ◽  
Point Of View ◽  
German Version ◽  
Profound Impact ◽  
Almost All ◽  
University Of Göttingen ◽  
The University ◽  
Modern Mathematics ◽  
Mathematics And Physics

The German version of Riemann’s Collected Works is confined to a single volume of 690 pages. Even so, this volume has had an abiding and profound impact on modern mathematics and physics, as we shall see. In fifteen years of activity, from 1851, when he gained his doctorate at the University of Göttingen, to his death in 1866, two months short of his fortieth birthday, Riemann contributed to almost all areas of mathematics. He perceived mathematics from the analytic point of view and used analysis to illuminate subjects as diverse as number theory and geometry. Although regarded principally as a mathematician Riemann had an abiding interest in physics and researched significantly in the methods of mathematical physics, particularly in the area of partial differential equations.

scholarly journals Social Order and Practical Wisdom of Walking in a Crowd

2018 ◽  
Vol 24 (4) ◽  
pp. 8-29
Author(s):  
Andrei M. Korbut
Keyword(s):  
Social Order ◽  
Practical Wisdom ◽  
Point Of View ◽  
Joint Production ◽  
Social Phenomena ◽  
Social Transformations ◽  
Sociological Approach ◽  
Everyday Practices ◽  
Phenomenal Field ◽  
Almost All

The article suggests returning to the “crowd” as an object of sociological analysis. Crowds have attracted early sociologists because crowds were visual embodiments of social forces that surpass individuals and also served as a symbol of the profound social transformations which were taking place in the late 19th and early 20th centuries. Analyzing crowds allowed for the first sociologists (G. Simmel, R. Park, M. Weber, E. Durkheim) to oppose the psychological interpretation of mass social phenomena with a purely sociological approach. However, in the second half of the 20th century sociologists had lost almost all interest in the crowd, as it did not meet the interests of researchers of “large” social structures, nor the interests of the proponents of interactionist approaches. This article shows that the crowd can again be made interesting for sociology if we were to consider it from the point of view of the everyday practices of the participants. In these everyday practices a specific form of phronesis, i.e. practical wisdom, technical skill coupled with moral judgment about which action is good and which is not, is implemented. It is shown here that the study of the practical wisdom of walking in a crowd requires special concepts and methods that can be found in phenomenology and ethnomethodology. The article suggests using three such concepts for the analysis of crowds: phenomenal field, oriented object, and figuration of details. With the help of these concepts, the methods of the crowd’s situated social order production are analyzed in relation to the management of speed and trajectories of movement, following one another, walkers’ stopping and slowing down, and joining the crowd. This analysis shows that the joint production of the crowd’s social order by its participants is a situated practice, i.e. it consists of making the local scenes of everyday life familiar and accountable, and of assessing the local adequacy of the actions performed.

scholarly journals SISI NEGATIF GAME ONLINE PERSPEKTIF ISLAM DAN PSIKOLOGI ISLAM

2021 ◽  
Vol 5 (2) ◽  
pp. 153
Author(s):  
Khotibul Umam ◽  
Abdul Muhid
Keyword(s):  
Literature Review ◽  
Life Style ◽  
Negative Impact ◽  
Technological Development ◽  
Human Life ◽  
Online Games ◽  
Point Of View ◽  
Technological Advances ◽  
Islamic Psychology ◽  
Almost All

Technological development has changed human life style. Child's world that was once filled with traditional games has now been eroded by technological advances. Nowadays online games that replace traditional games are not only favored by children, almost all levels of human age like playing online games. But behind it all there is a negative impact that haunts its users. This study aims to reveal the negative side of using online games from the point of view of Islam and Islamic Psychology. The technique used is literature review by compiling some previous articles. The results showed that excessive use of online games will give a bad impact on the physical and psychological users, such as visual impairment, sleep disturbance, addiction, violence and stress. The use of online games is also considered more disadvantage than the benefits and it’s seen as an activity that wastes time, and it is prohibited in Islam.

scholarly journals Complexes for continuous monitoring of drilling fluid parameters during drilling

2021 ◽  
Vol 6 (3) ◽  
pp. 144-151
Author(s):  
Sergey V. Lakhtionov ◽  
Ivan S. Chumakov ◽  
Sergey G. Filinkov ◽  
Dmitry M. Chukin ◽  
Evgeny N. Ishmetyev
Keyword(s):  
Continuous Monitoring ◽  
Drilling Fluid ◽  
Point Of View ◽  
Complete Analysis ◽  
Drilling Fluids ◽  
Automatic Mode ◽  
Design Values ◽  
Drilling Rigs ◽  
Almost All ◽  
Fluid Parameters

Background. The article provides an overview of existing complexes (units) for continuous monitoring of drilling fluid parameters in automatic mode. Aim. To justify the need to develop a complex (module) that will allow combining existing technologies and making a step forward in the field of process automation in terms of monitoring the parameters of drilling fluids. Materials and methods. In the current realities of well construction, the control of drilling fluid parameters on almost all drilling rigs operating on the territory of Russia (possibly with the exception of a few off shore projects) is carried out by the work of a solution engineer, usually a representative of a service company. The analysis of the parameters, depending on the number of personnel, the speed of penetration, the complexity or importance of the well, can be carried out from 2 to 6 times a day [1, 2]. This means a complete analysis, rather than monitoring the density and conditional viscosity, which can be measured by a representative of the drilling crew, for rapid response, and with greater frequency. Due to such a low measurement discreteness, there is a high probability of a significant deviation of the drilling fluid parameters from the design values. As a result, the probability of various complications, both geological and technological, increase significantly. Results. During the analysis of information from open sources, the most promising complexes (modules) from the point of view of application in the current conditions were identified, their positive and negative sides were evaluated. As a result of the conducted review of open sources, the most promising complexes (modules) in terms of application in the current conditions are identified, the positive and negative sides of the systems under consideration are displayed, and the need to develop a complex (module) that will combine all the best that is available today and make a qualitative step forward in the field of “peopleless” technologies used during drilling wells in terms of monitoring the parameters of drilling fluids is justified. Conclusions. The necessity of developing a complex (module) for automating processes in terms of monitoring the parameters of drilling fluids is justified.

scholarly journals Antonio Chamorro Daza (1903-2003): Scientific production during the first years of exile (1937-1945)

2021 ◽  
Vol 106 (106(812)) ◽  
pp. 44-53
Author(s):  
E. Barranco-Castillo ◽  
I. Melgares-Moreno ◽  
F. Girón-Irueste
Keyword(s):  
Research Work ◽  
Scientific Production ◽  
Point Of View ◽  
Google Scholar ◽  
Important Research ◽  
Research Institutions ◽  
Endocrine Glands ◽  
Practical Point ◽  
Metasearch Engine ◽  
Almost All

Objetives: The main aim of our work is to highlight the importance of Chamorro’s discoveries in the fields of endocrinology, gynaecology, reproduction and oncology. Methods: Evaluation of the bibliometric impact of Chamorro’s work using Google Scholar, PubMed, Scopus and Gallica. Results: Between 1937 and 1945 Chamorro carried out important research work, the results of which provided valuable discoveries about the activity of the main endocrine glands. Discussion: To achieve our objective, Google Scholar has been the most profitable metasearch engine from a practical point of view, having recognized almost all of the articles published by Chamorro, although having ignored some of them it could be thought that the overall impact of this author is higher than that which has been found. Conclusions: These findings were reflected in the most prestigious journals and widely disseminated in U.S. research institutions, amongst others. In Spain, however, they were ignored. Maybe it’s time to spread it.

Characteristic of basic tools of mobile learning in informatics

2021 ◽  
pp. 9-13
Author(s):  
I. V. Izhdeneva
Keyword(s):  
Mobile Devices ◽  
Mobile Learning ◽  
Cognitive Activity ◽  
Point Of View ◽  
Learning Tools ◽  
Difficult Situation ◽  
Characteristic Features ◽  
Definition Of ◽  
Almost All ◽  
Educational Potential

The article actualizes the possibilities of mobile learning based on the use of mobile devices and technologies available to almost all students. Various approaches to the definition of the concept of "mobile learning" are analyzed, including techno-centric and information-centric approaches. The concept of mobility as one of the attributes of learning tools is revealed. The importance of mobile learning in the current difficult situation of distance learning during the pandemic is substantiated. The characteristic features of mobile learning are highlighted, affecting its main functions, learning tools and independence from the time and place of learning. Possible directions for the implementation of mobile learning are characterized, from simple transfer of educational content to compliance with basic educational theories. From the point of view of the functioning and directions of development of mobile learning, its basic principles in teaching informatics are formulated. The types of students' activities are briefly characterized; some advantages of mobile learning are highlighted and its features as visualization, interactivity, efficiency of use in teaching children with disabilities are characterized. Some popular educational apps for mobile devices are considered, their characteristics are given, and their educational potential is revealed. Examples of mobile applications are given, the use of which in informatics lessons will help to activate the educational and cognitive activity of students and stimulate them to engage in informatics, coding and robotics.

Analyzing Growth Trends of Reusable Software Components

2013 ◽  
pp. 40-54 ◽  
Author(s):  
Kuljit Kaur
Keyword(s):  
Software Evolution ◽  
Point Of View ◽  
Software Components ◽  
Data Set ◽  
Reusable Components ◽  
Reusable Software ◽  
Evolution Analysis ◽  
Software Modules ◽  
Almost All ◽  
Monitoring Software

Reusable software components are the software modules that can be (re)used across a number of applications in a particular domain. Component users prefer to use those components which can be adapted easily for their changing requirements. So components have to evolve continuously in order to attract users. This chapter focuses on the evolutionary aspects of software components. It mentions various techniques for monitoring software evolution. It uses metrics based analysis as the technique to show software evolution of 15 reusable components from the point of view of their size, complexity, and functionality. The evolution analysis is motivated by laws of software evolution which suggest that as software ages, it increases in size and complexity (unless it is managed) and it has to offer increased functionality to please its users. The findings of the study indicate that the size of the software components (in this data set) grows at a linear rate, and complexity is well managed. However, increase in functionality is sub linear for almost all the components. It remains almost constant for some of them.

Treatment of large and ptotic breasts

2021 ◽  
pp. 1367-1372
Author(s):  
Adam Searle ◽  
Albert de Mey ◽  
Christophe Zirak
Keyword(s):  
Surgical Techniques ◽  
Point Of View ◽  
Vertical Scar ◽  
Areolar Complex ◽  
Psychological Point ◽  
Ptotic Breasts ◽  
Almost All ◽  
Normal Sensitivity ◽  
Wise Pattern

The breasts have always been considered a sign of femininity. The correction of breast deformities is therefore important from a physical and psychological point of view, improving greatly the quality of life. Many surgical techniques have been proposed to correct the shape and volume of the breast, and in recent decades techniques have been proposed to preserve the nipple sensitivity and increase the vascular safety of the procedure. Templates (such as the Wise pattern) have been proposed to improve planning and different pedicles for the areola have been described. During the last 20 years, new techniques have been introduced to minimize scars, leaving normal sensitivity in almost all cases, the possibility of lactation, and a pleasing shape. The periareolar scar is, unfortunately, always necessary to reposition the nipple–areolar complex. The vertical scar is necessary to resect the excess of skin of the lower pole of the breast. Effort has been directed to reduce or eliminate the horizontal submammary scar, leading to a vertical scar only, even in large reductions.

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