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To understand new facets of situated freedom, this study explores the socio-cultural process of 'freedom' in everyday situations from the trajectory equifinality approach (TEA) perspective. The concept is important for TEA, which describes aspects of 'free' choice as constructed through communication between self and society. This study elaborates on and enriches the argument of the situated freedom by considering the authors' shared experience (bifurcation point; BFP) using the three layers model of genesis (TLMG). Consequently, we depict that freedom is not only located within a situation but also in semiotic communication. Situated freedom for the authors in BFP involves semiotic communication, including imagining the hyper-generalised affective semiotic field for others, represented by the flow of feelings 'comfort for all'. Amanogawa (the Milky Way), an organic metaphor for the TLMG mountain range, extends this idea. This study demonstrates how freedom-related feelings experienced by the authors emerge in the communication of their socio-cultural context. The Amanogawa metaphor in the TLMG, which bridges the self and society, provides a richer illustration of the semiotic communication between systems in the BFP. [ABSTRACT FROM AUTHOR]

The paper describes the method and procedure for determining the bifurcation point in the technological process, at which the transition of a system to a critical (emergency) state is most likely. The method of a double sliding window is briefly described, which allows detecting anomalies in a continuous multidimensional flow of information generated by sensors of technological equipment. The description of the software and technical platform for the analysis of streaming data is given. [ABSTRACT FROM AUTHOR]

In this paper, we study the existence of nodal solutions of some nonlinear boundary value problems for ordinary differential equations of fourth order with a spectral parameter in the boundary condition. To do this, we first study the global bifurcation of solutions from zero and infinity of the corresponding nonlinear eigenvalue problems in classes with a fixed oscillation count. Then, using these global bifurcation results, we prove the existence of solutions of the considered nonlinear boundary value problems with a fixed number of nodes.

Copyright of Environmental & Social Management Journal / Revista de Gestão Social e Ambiental is the property of Environmental & Social Management Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, based on some prior estimates, we show that the essential spectrum λ = 0 is a bifurcation point for a superlinear elliptic equation with only local conditions, which generalizes a series of earlier results on an open problem proposed by Stuart (1983). [ABSTRACT FROM AUTHOR]

The geometrical diversion of combustible gas molecules notably affects their self-ignition in high-pressure tubes. This study investigates the propagation of shock waves and flame induced by a sudden pressure release of hydrogen in various Y-shaped tubes. The impact of the initial burst pressure, downstream tube length, and bifurcation angle (60°, 120°) were analyzed by recording the pressure signals, photoelectric curves, and jet fire evolution. The results showed that the gas diversion caused by the Y-shaped structure significantly reduces the maximum overpressure of the hydrogen jet, the intensity, and the velocity of the leading shock wave. Also, it was indicated that increasing the Y-shaped tube's length downstream of the bifurcation point could enhance the strength of leading and reflected shock waves after the Y-bifurcation, making self-ignition more likely to happen. Applying a 60°-bifurcation angle could create stronger leading and reflected shock waves during the propagation downstream of the bifurcation point, while a 120°-bifurcation angle could make a more substantial reflected shock wave propagating upstream. It leads to the re-ignition downstream of the bifurcation in the 60°-bifurcation tube after the flame quenching and stronger far-field jet fire outside the tube. • The impact of geometrical diversion of pressurized hydrogen was investigated. • The influence of tube length and bifurcation angle were analyzed. • The flame quenching and re-ignition were explored. • The evolution of double far-field jet fire was recorded. [ABSTRACT FROM AUTHOR]

We study the bifurcation of solutions from infinity of Sturm–Liouville eigenvalue problems with a spectral parameter in the boundary condition. These problems are reduced to integro-differential equations to which the global bifurcation theory can be applied. Using this, we show the existence of two families of unbounded continua of solutions to these problems, emanating from bifurcation points and lying in classes of functions with fixed oscillation count in a neighborhood of these bifurcation points. [ABSTRACT FROM AUTHOR]

In this paper, we consider nondifferentiable perturbations of a half-linear eigenvalue problems for ordinary differential equations of fourth order. The global bifurcation of these non-linear problems from the line of trivial solutions is studied. We prove the existence of two families of unbounded connected components of the solution set of these problems, bifurcating from some intervals of the line of trivial solutions and contained in classes of functions having nodal properties of halfeigenfunctions (and their derivatives) of a half-linear eigenvalue problems obtained from these nonlinear problems by equating the nonlinear terms to zero. [ABSTRACT FROM AUTHOR]

The article studies the collapse of Rzeczpospolita and the admission of its parts into the Russian and Austrian Empires to understand through the institutionalist approach the consequences of reformatting the geopolitical space, namely, implantation of the debris of the collapsed society into another social system. It reveals the mechanisms of the fusion of donor and recipient societies. They include unification – the integration of new territories into the legal and administrative-territorial organization of the acceptor country. This mechanism proceeds through several stages: initial, implying the creation of hybrid institutions (implementation of the new authorities into the pre-existing system of power); secondary, when the institutional transplants are rebuilt with the simultaneous foundation of intermediate institutions); final (the ultimate restructuring of power following the new model). A vital instrument of unification is constituted by estate homogenization or the alignment of the social organization of the new lands and the acceptor society. Besides, among the mechanisms of integration, there are conditionality (positive, or stimulating, for extending the social base of transformations as well as negative, intended to curb resentment), substitution (admission of representatives of the acceptor society to the higher estate of the new lands),socialization (measures to culturally homogenize the united social system). Despite the similarity of the employed mechanisms, there is a difference in the integration models applied by the Russian and Austrian Empires, which is due to the specificities of the state organization and national structure of these empires as well as the geographical location and the level of economic development of the acquired territories. The distinctive feature of the Russian approach to homogenization of the new lands with the rest of the empire was transplantation of economic, political, and social-cultural institutions to the acquired territories with preservation of some pre-existing endemic economic institutions. The Austrian policy was haracterized by asymmetrical and limited institutional transplantations (only political institutions) to the new province, which turned the region into a virtual inner colony. The meaning of the chosen integration model for the later development of the integrated lands is also discussed.

This paper investigates the relationship between synchronization, system dynamics, and bifurcation points. To investigate the synchronization of dynamical systems, first, two oscillators are considered. Then networks with different structures are generated. The Master Stability Function (MSF) and synchronization criterion are computed for various oscillator dynamics in each network. The results of this paper can be categorized into two groups. In the first group, three points around the bifurcation points of the systems (before, near, and after the bifurcation point) are investigated that show no specific variation in the MSF diagram or its zero-crossing. Then it is revealed that the zero-crossing of the MSF diagram is related to the bifurcation points of the synchronization measure. In the second group, the types of synchronization transitions and MSFs for two periodic and chaotic dynamics of the studied systems are investigated for different networks. The results show that the type of synchronization transition can be different by changing the dynamics or network structure. However, in all networks and dynamics, the zero-crossing of MSF is completely matched with the bifurcation points of synchronization measure. [ABSTRACT FROM AUTHOR]

In this paper, we consider bifurcation from zero or infinity of nontrivial solutions of the nonlinear Sturm–Liouville problem with indefinite weight. This problem is mainly important because of it is related with a selection-migration model in genetic population. We show the existence of four families of unbounded continua of nontrivial solutions to this problem bifurcating from intervals of the line of trivial solutions or the line $\mathbb{R} \times \{\infty\}$ (these intervals are called bifurcation intervals). Moreover, these global continua have the usual nodal properties in some neighborhoods of bifurcation intervals.

The paper considers the mathematical formulation of the problem of transverse oscillations of a vertical rod under gravity, friction and external pulse effect, leading to thermal expansion of the rod. The dynamics of the system under consideration corresponds to the behavior of a fuel element (FE) in a pulsed reactor and is related to the dynamic stability of the processes occurring in it. The FE dynamics is described by inhomogeneous linear differential equation of the fourth order with non-constant coefficients. Initial boundary conditions are not smooth since they correspond to the instant heating of the part of the FE surface exposed to neutron pulse radiation. The general solution of the homogeneous linear equation can be found using the concept of generalized functions expressed as a series expansion in terms of coordinate eigenfunctions dependent on p parameter. The p parameter is related with the FE mass and at some certain values results in bifurcation points of the boundary value problem for eigenfunctions. The partial solution can be found in several ways: using the Fourier transform, the method of Green's function, and in terms of series expansion by eigenfunctions. Eigenfunction expansion coefficients in an explicit form have been obtained and the numerical solution accuracy has been estimated for some important particular cases. The results of the obtained exact solutions appear to be very close to the results of the ANSYS numerical estimations. In the future the obtained exact solutions will be used as input data to simulate self-consistent system dynamics of more than 400 FE. Therefore, the advantage of the exact solution in practical use is that its calculation is much faster as compared with the finite element method done with ANSYS. [ABSTRACT FROM AUTHOR]

The article considers the main approaches to the development and evaluation of the organization’s logistics strategy based on the application of bifurcation theory. The paper notes that the greatest competitive advantages in the process of carrying out activities can be obtained by the company when designing a unique logistics strategy based on the individual features of the organization’s logistics system. The authors reveal that the bifurcation theory allows you to determine the conditionality of a qualitative dynamic change in the behavior of a logistics system by an infinitesimal change in certain parameters of the system. As part of the assessment of the organization’s logistics management strategy, bifurcation theory forms the basis for determining shift in the qualitative parameter of the system and makes it possible to assess the effect of this parameter on the behavior of the entire system as a whole and each functional subsystem separately. The study reflects that it is possible to determine the critical values of individual variables, when overcoming which the logistics system itself goes into unstable state. The main concept defining the process of critical transition of the state of the logistic system is the bifurcation point.

Представлено исследование мотивов и факторов профессионального выбора как одной из характеристик профессионального самоопределения студенческой молодежи. Материалом послужили исследования 1990-х гг. ученых Е. А. Климова, Н. В. Кузьминой, В. А. Сластенина, Г. Н. Пашкевич и проведенное авторами в октябре 2019 г. анкетирование студентов 1-го курса Томского государственного педагогического университета. Исследование проводилось на основе теоретических (анализ научной литературы и статистических данных приемной кампании 2019 г.) и эмпирических (анкетирование студентов) методов. Цель статьи – представить педагогическому сообществу факторы, влияющие на профессиональный выбор студентов-первокурсников, ставших участниками исследования 2019 г., в сравнении с исследованиями в этой области периода 1990-х гг. Были сделаны следующие выводы: получение педагогической профессии остается наиболее привлекательным для девушек; сохраняется внутригосударственная и международная образовательная миграция абитуриентов; довузовский педагогический опыт помогает сделать осознанный выбор направления подготовки в педагогическом вузе; у современных студентов-первокурсников присутствуют внутренние мотивы, но преобладают положительные внешние. По сравнению с исследованиями В. А. Сластенина, увеличился процент студентов, которые отнесли к факторам, повлиявшим на выбор педагогического вуза, факторы «желание получить высшее образование» и «так сложились обстоятельства», что дает основание говорить об актуальности содействия в профессиональном самоопределении студентов в период обучения в вузе.

The article is aimed at developing a methodical approach to determining the acceptable level of threats and risks in the activities of industrial enterprise as the initial parameters of bifurcation points. The article stipulates that the enterprise management system faces not only the issue of increasing the promptness of decision-making and finding new approaches to timely identification of the impact of risks on the main performance of enterprise, but also the issue of identifying the impact of possible risks on the evolution or revolution of either development, or degradation of the enterprise, as well as the transformation of these movements either in a certain order or in the chaos of functioning. In the course of research a methodical approach to risks management in the system of security of the enterprises’ development is proposed and an acceptable level of threats and risks in the activities of industrial enterprise as the initial point of bifurcation is defined. For the mechanism of forming alternative solutions regarding the acceptable level of threats and security risks of the enterprise’s development it is proposed to use the PDSA-cycle (Plan – Do – Study – Act = planning – implementation – study – reaction) consistently for each functional constituent of the enterprise’s activities, depending on the stages of its life cycle. Based on the selected list of possible threats to the enterprise’s activities and for each functional constituent, a model of integral assessment of the enterprise’s risk in the enterprise’s development security system and the probability of occurring risks with determining the range of their degree is proposed, which in the future will allow to determine the points of bifurcation in the system of management of the enterprise’s activities.

Precision data of the accurate calorimetric measurements of phase equilibria for ternary mixtures of methane, propane, and octane especially for the low concentration of octane have been presented. Based on the experimental data of heat capacity, internal energy, pressure, and temperature derivative of pressure at constant volume, the phase diagrams have been plotted in the range 140–350 K and 0.1–24 MPa. Phase transitions are localized by the finite discontinuities in temperature derivatives of the thermodynamic potentials. Our investigations show that hydrocarbon mixtures for the low concentration of octane split into two phases, the macrophase enriched by methane and propane and the octane-rich microphase. Besides, octane provokes a split of the liquid part of the macrophase into two liquid phases, the octane-rich phase and the octane-lean phase. To prove that all phases are equilibrium phases a cooling mode of measurements is used. At the cooling mode of measurements the same phase transitions as at the heating mode occur. These phase transitions correspond to the formation of the octane-rich microphase and the macrophase enriched by methane and propane. Besides, at the cooling mode of measurements a split of the liquid part of the macrophase into two liquid phases takes place. [ABSTRACT FROM AUTHOR]

Investigating the dynamical properties of mechanical systems has been an attractive topic recently. In this paper, the dynamical properties of an impact oscillator are studied. The impact oscillator is a non-autonomous system with possible chaotic attractors. The oscillator without external force has a stable equilibrium. Bifurcation analysis of the system shows various dynamics by changing the frequency ratio of external force. In addition, plotting bifurcation diagrams with different methods indicates the system's multistability. The bifurcation points of the system are studied. Prediction of bifurcation points is critical since it can cause unwanted qualitative changes in the dynamic of the system. Autocorrelation and Lyapunov exponent are used in the prediction of the bifurcation points of this system. [ABSTRACT FROM AUTHOR]

In this paper, we study the nonlinear eigenvalue problem for ordinary differential equations of fourth order with a spectral parameter in the boundary condition. Global bifurcation of nontrivial solutions of this problem is investigated. We prove the existence of two families of unbounded continua of the set of solutions to this problem bifurcating from points and intervals of the line of trivial solutions. Moreover, it is shown that these continua are contained in classes of functions possessing oscillating properties of the eigenfunctions of the corresponding linear problem and their derivatives. [ABSTRACT FROM AUTHOR]

In this paper, we consider bifurcation from zero or infinity of nontrivial solutions of the nonlinear Sturm-Liouville problem with indefinite weight. This problem is mainly important because of it is related with a selection-migration model in genetic population. We show the existence of four families of unbounded continua of nontrivial solutions to this problem bifurcating from intervals of the line of trivial solutions or the line R × {∞} (these intervals are called bifurcation intervals). Moreover, these global continua have the usual nodal properties in some neighborhoods of bifurcation intervals. [ABSTRACT FROM AUTHOR]

The effect of the coil on the dynamical behavior of the electronic circuit with nonlinear part memductance was studied, where we studied four coil values: L = 90mH, L = 80mH, L = 70mH and L = 100mH with changing the value of the first capacitance c1. We obtained stability maps consisting of two regions (the dynamical behavior zone and the stability zone), where the dividing line is the Hopf bifurcation line, as well as the bifurcation diagram for each value from the coil and the first capacitance was obtained, as well as the phase portrait diagram in which we obtained the chaotic attractions And the period of the first, second, third, fourth, fifth, sixth and eighth. [ABSTRACT FROM AUTHOR]

In this paper, we consider the nonlinear Sturm-Liouville problem with an indefinite weight and a spectral parameter in the boundary condition. We establish the existence of four families of global solutions branches bifurcating from the points of the line of trivial solutions and possessing the usual oscillation properties. [ABSTRACT FROM AUTHOR]

In this article, we study the global bifurcation from infinity of nonlinear eigenvalue problems for ordinary differential equations of fourth order. We prove the existence of unbounded continua of solutions emanating from asymptotically bifurcation points and intervals and having the usual nodal properties near these points and intervals.

An analysis based on an elementary theory of plane curves is presented to locate bifurcation points from a main component in the parameter space of a family of optimal fourth-order multiple-root finders. We explore the basic dynamics of the iterative multiple-root finders under the Möbius conjugacy map on the Riemann sphere. A linear stability theory on local bifurcations is developed from the viewpoint of an arbitrarily small perturbation about the fixed point of the iterative map with a control parameter. Invariant conjugacy properties are established for the fixed point and its multiplier. The parameter spaces and dynamical planes are investigated to analyze the underlying dynamics behind the iterative map. Numerical experiments support the theory of locating bifurcation points of satellite and primitive components in the parameter space. [ABSTRACT FROM AUTHOR]

Recent mathematical results for the noisy Kuramoto model on a 2-community network may explain some phenomena observed in the functioning of the suprachiasmatic nucleus (SCN). Specifically, these findings might explain the types of transitions to a state of the SCN in which 2 components are dissociated in phase, for example, in phase splitting. In contrast to previous studies, which required additional time-delayed coupling or large variation in the coupling strengths and other variations in the 2-community model to exhibit the phase-split state, this model requires only the 2-community structure of the SCN to be present. Our model shows that a change in the communication strengths within and between the communities due to external conditions, which changes the excitation-inhibition (E/I) balance of the SCN, may result in the SCN entering an unstable state. With this altered E/I balance, the SCN would try to find a new stable state, which might in some circumstances be the split state. This shows that the 2-community noisy Kuramoto model can help understand the mechanisms of the SCN and explain differences in behavior based on actual E/I balance. [ABSTRACT FROM AUTHOR]

In this paper, we present dynamical viewpoints under the Möbius conjugacy map on the Riemann sphere for a uniparametric family of optimal eighth-order multiple-root finders. Various conjugacy properties are investigated including the invariance of the fixed point and its multiplier, which enables the family of iterative methods to trace along the consistent orbits in position. The parameter spaces and dynamical planes are studied and illustrated to visualize the periodic components and their geometric properties. Both theoretical and computational analyses along with a numerical algorithm are carried out regarding the bifurcation points of satellite and primitive components. [ABSTRACT FROM AUTHOR]

Time dependences of projective coatings for different ecotopes of soil-plant communities on pastures in arid zones are obtained by numerical dynamic modeling in the form of ordinary differential equations. The models are developed for the dynamics of the functioning of four types of phytocenoses with different interaction schemes. The variety of schemes of succession transitions is caused by biological diversity and determines the mechanisms of self-organization of soil-plant ecosystems. The interaction between ecotopes in dynamic models is described by a matrix of mutual successional transitions between them. A computational experiment technique is developed to construct the evolution of such transitions and identify bifurcation points. The dependence of evolutionary processes on the complexity of internal connections in the ecosystem was found. It is shown that the self-recovery ability of pasture plant communities is associated with the diversity of their phytocenoses. Synergetic provisions of phytocenoses' joint development in the regime of succession transitions are formulated. [ABSTRACT FROM AUTHOR]

Copyright of Metallophysics & Advanced Technologies / Metallofizika i Novejsie Tehnologii is the property of G.V. Kurdyumov Institute for Metal Physics, N.A.S.U and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We consider nonlinearizable Sturm-Liouville problem indefinite weight function. We show the existence of two pairs of global continua emanating from the bifurcation intervals surrounding the principal eigenvalues of the corresponding linear problem and contained in the classes of positive and negative functions. [ABSTRACT FROM AUTHOR]

We perform numerical simulations to investigate the hysteresis phenomenon near the bifurcation points of the synchronization region leading to vortex-induced vibrations. We characterize the response using nonlinear dynamics tools. We find an unstable region at both ends of the synchronization regime where the response depends on initial conditions. Unlike previous studies, the focus of the current research is to analyze the effect of the structure's initial condition on the VIV response. We vary the initial velocity of the cylinder and observe the response of transverse displacement and lift coefficient as a function of Reynolds number. We observe that in the pre-synchronous and synchronous regimes, the cylinder response is always period-1 at cylinder's natural frequency. However, in the post-synchronous regime, the response is period-n where n > 1 . Thus, bifurcation diagrams depicts the variation of the onset of synchronization and its spectrum over the range of Reynolds number. [ABSTRACT FROM AUTHOR]

A numerical investigation of the problem of geometrically nonlinear axisymmetric deformation of a sandwich cylindrical shell with a transversally soft core reinforced in the end sections by elastic rods has been carried out. To describe the process of deformation, we have used the previously derived equations of the refined geometrically nonlinear theory that allow to both study the subcritical behavior of the shell and to reveal all possible buckling forms of the carrier layers. These equations are based on the introduction, as unknown variables, of the contact force of the interaction of the outer layers with the core, as well as of the outer layers and the filler with the reinforcing bodies at all points on the surfaces of their conjugation. Numerical methods for solving the formulated problems have been developed. They are based on the preliminary reduction of the original problems to a system of integro-algebraic equations, for the solving of which the finite sum method is used. A method has been proposed for investigating the subcritical and supercritical geometrically nonlinear behavior of a shell with its end compression through contour reinforcing rods, according to which unstable equilibrium positions are determined by the method of continuation of the solution with respect to the parameter when the external forces are selected as a parameter. A method has been proposed for finding the critical load (the bifurcation point) at which the shell buckling occurs. This method is based on the linearization of the initial geometrically nonlinear problem in the neighborhood of its nonlinear solution, followed by the formulation of the eigenvalue problem with a nonlinear presence of the parameter. The results of the numerical experiments have been discussed. The results of the experiments have been analyzed.

We consider a nonlinearizable eigenvalue problem for the beam equation with an indefinite weight function. We investigate the structure of bifurcation set and study the behavior of connected components of the solution set bifurcating from the line of trivial solutions and contained in the classes of positive and negative functions.

The objective of this paper is to study the existence, multiplicity and non existence of solutions for semilinear elliptic problems under a local Landesman–Lazer condition. There is no growth restriction at infinity on the nonlinear term and it may change sign. In order to establish the existence of solution we combine the Lyapunov–Schmidt reduction method with truncation and approximation arguments via bootstrap methods. In our applications we also consider the existence of a bifurcation point which may have multiple positive solutions for a fixed value of the parameters. [ABSTRACT FROM AUTHOR]

In this paper, the authors establish the global structure of one-signed periodic solutions of the first-order functional differential equation u ′ (t) = a (t) u (t) - λ f (t , u (t - τ (t))) , t ∈ R by using unilateral bifurcation theorem, where the nonlinearity f ∈ C (R × R , R) is T-periodic with first variable and having nontrivial zeros, a ∈ C (R , [ 0 , ∞)) is T-periodic function with ∫ 0 T a (t) d t > 0 , τ ∈ C (R , R) is T-periodic function, λ > 0 is a parameter. [ABSTRACT FROM AUTHOR]