Synchronization in Chains of Material Particles with Non-linear Features Julijana D. Simonovic Doctor of Tehnical Sciences University of Nis Faculty of Mechanical Engineering The paper presents the marvelous possibilities of identical synchronization in the dynamics of the chains of material particles. The nature of coupling elements between particles has got damped, linear and non-linear elastic properties. The one or more particles in the chain are periodically forced. Depending of coupling elements features and the positions of excitations the synchronization effect is less or more present. The multi-parameters analyses were done by presentation of numerical simulation in the phase space of output variables of coupled particles. Concluding remarks have been considered about nature of coupling and symmetries in system of the external excitation positions that are necessary and enough for reaching the identical synchronization threshold. Keywords: chain of material particles, coupling elements, identical synchronization, synchronization threshold, , multi-parameters analyses. 1. INTRODUCTION It would not be too much of an exaggeration to say that oscillations are one of the main forms of motion. They range from the periodic motion of planets to random openings of ion channels in cell membranes. The chain of material particles coupled with elastic and damped elements periodically forced performs oscillatory motions with all characteristic phenomena like as dynamical absorption, resonance, beating, modulations, synchronisations and could be used like a model of various natural phenomena. Nature is not based on isolated individual systems. It is rich in connections, interactions and communications of different kinds that are complex beyond belief. With this, synchronization is the most fundamental phenomenon associated with oscillations. Chains of material particles with non-linear coupling are systems with pronounced nonlinear characteristics. When one couple material particles that oscillates a lot of things can happen. For example, oscillations can stop altogether, which might be good sometimes, but occasionally disastrous. Or they could become totally unpredictable-but you might like it nevertheless because it looks beautiful. But the phenomenon which is most often associated with synchronization is the change of the time scales of interacting systems: if one couples the systems cleverly, they can start to oscillate “syn-chronously,” which means “sharing the same time” [1]. The nonlinearity brings the properties of exponentially divergence of trajectories of particles that starts from very close points in phase space, nevertheless even in that systems on may find synchronization, which is rather surprising detail [1-2]. In the general sense the synchronization consider the correlation or mutual response in time behaviour of two or more processes. In other words, regimes of Received: May 2014, Accepted: November 2014 Correspondence to: Julijana Simonovic University of Nis Mechanical Engineering Faculty , Medvedeva A. 14, 18000 Nis, Serbia E-mail: [email protected] doi:10.5937/fmet1404341S © Faculty of Mechanical Engineering, Belgrade. All rights reserved subsystems have to coincidence after some period of time [3-4]. One can say that synchronization is the most fundamental phenomenon that occurs in oscillating processes. In most general terms, synchronization can be defined as an adjustment of the time scales of oscillations due to interaction between the oscillating processes, [5].Investigation of dynamics of chains of material particles in the systems with more than three degrees of freedom, even in the field of classical and linear chain forced dynamics, is important not only for mechanical signal processing, but also for electrical signal processing and signal filtering, for processing biodynamical signals in life systems (DNA double helix chains [6], biodynamical chain oscillators [7-8]) and also for university teaching and integrations of scientific results in different scientific fields. This paper presents possibilities of identical synchronization (IS) in the non-linear chains of material particles. First of all we present model of synchronization of two material particles coupled with damped and linear and non-linear elastic elements that is mathematically tractable. Our experience tells us that models with the latter property are exceptional. While the treatment of just a two coupled elements can be done within the framework of non-linear dynamical systems, the description becomes much more complicated for a large number of such elements. Considering that in the next section we use multiparametric numerical simulations by using the possibilities of the Mathematica software for crossed chains with nine material particles. Depending of values of coupling coefficient and the positions of the external excitation the effect of synchronization is less or more present. After all, few conclusions about the nature of coupling like as necessary strength of coupling coefficients which is needed and enough for IS in the particular chain systems were discussed. From all different cases of synchronization the identical synchronization (IS), as a particular case of general synchronization, was been of interest in this paper as in the paper [9]. The most simply case of IS could be bring off when the particles are coupled with sufficient FME Transactions (2014) 42, 341-345 341 coupling strength so that their states are equal after transient changes. The work was originally presented on the 1st International Symposium on Machines, Mechanics and Mechatronics (SMMM 2014),on July 1-2. 2014, University of Belgrade, Faculty of Mechanical Engineering,Serbia. 2. MATHEMATICAL MODELING x1 t F1 t F1 cos 1t 0 m1 x 2 t b c, c~ a1 t 1 a1 t F2 t F2 cos 2t 0 m2 1 t p̂1 1 a 2 t 2 a 2 t Mathematical modelling can assist in formulating hypotheses and finding the experiments that may differentiate between different mechanisms, can help in determining which of the assumed mechanisms is likely to be most important for the observed effects. Finally, and perhaps most importantly, mathematical modelling is the tool for synthesis-the process of combining separate elements in order to form a coherent wholeallowing reconstruction of the function of phenomena as a whole based on the acquired knowledge of elementary processes. The basic model of forced non-linear oscillations of two material object with mass m1 and m2 that are coupled with elements of damped and elastic properties, Fig.1. The elastic coupling element has both linear and nonlinear parts, the non-linear part is introduced like a nonlinearity of third order. amplitudes and phases in the first asymptotic averaged approximation [10] may be rewriten in the general form as follow: P1 cos 1 P1 3 1 2 1 1 2 a1 t a 2 t sin 1 p̂1 a1 t 1 8 p̂1 4 p̂1 2 t p̂ 2 2 p̂ 1 1 P2 2 p̂ 2 (3) cos 2 P2 3 2 2 1 2 2 sin a 2 t a1 t 2 p̂ 2 a 2 t 2 8 p̂ 2 4 p̂ 2 The full forms of constants i , i , i and Pi could be find using the proposed method. Here it was underlined that these constants all rely on coefficients of coupling properties via cofactors K 2si , that i depends of damping coefficients of visco-elastic layer, ~i and Pi depend of excited amplitudes, and i , i of non-linearity layer properties. Coefficients i are coefficients of mode mutual interactions. When we finally find the closed forms of solutions then we are in position to make conclusions about IS. If we denoted with x1 , x1 ,... and x2 , x 2 ,... the sets of dynamics variables which corresponds to the states of first and second oscillators, respectively, than the identical synchronization occurs when, for sets of initial conditions x1 0, x2 0,... and x2 0, x 2 0,... , the difference of state variables x2 t x1 t 0 when time t or in the form: Figure 1. Periodically forced chain of two material particles coupled with an element with damped, linear and nonlinear properties. x2 t x1 t 0 lim t The system of the two coupled nonlinear differential equations that corresponde to this model is: This practically means that after enough period of time the dynamics of oscillators becomes the same xi 1 t xi t for i 1,2,..., n in proper approximation. This equality in the unique state space presents subspace (diagonal), and that equality represents convergence of space vector xt to that diagonal set x : xi 1 xi , [4]. x1 t 2 1 x 2 t x1 t 12 x2 t x1 t 1 x2 t x1 t 3 f 1 t x2 t 2 2 x 2 t x1 t 22 x 2 t x1 t 2 x 2 t x1 t 3 f 2 t (1) where we use notation for the coefficients: of non-linear coupling i c~ mi , of linear coupling i2 c mi , of damped coupling. The functions of periodic excitation are f i t Fi mi cosi t i . Proposed forms of the solutions are: xi t as t K 2si cos s t (2) With the unknown time depended amplitudes ˆ as t Rs t e t and phase s t s t s t , where i are: K 2si co-factors of determinant corresponding to basic homegenous coupled system , ˆi and p̂i are real and imaginary parts of the appropriate pair of the roots of the characteristic equation (see Ref. [10]). Amplitudes a s t and phases s t may be obtained by using the Krilov-Bogolyubov-Mitropolyskiy asymptotic method, if it was taken into account that defined task satisfies all necessary conditions for applying asymptotic method Krilov-Bogolyubov-Mitropolskiy concerning small parameter . The system of the first order differential equations according to unknown 342 ▪ VOL. 42, No 4, 2014 . (4) While the treatment of just a two coupled elements can be done within the framework of non-linear dynamical systems, the description becomes much more complicated for a large number of such elements. The next model of interests is the model of chain lattice composed of the four chains with eleven material particles. The chains are orthogonally crossed on the third and the ninth particles noted as a knots, so there is two horizontal and two vertical chains, Fig. 2. Now we have forty four coupled equations of motions in the form: 3 3 mu uij cu ui 1. j 2ui . j ui 1. j c~u ui 1. j ui . j c~u ui . j ui 1. j bu ui 1. j 2ui . j ui 1. j hUi , j cos ij t ij for i 1..4, j 1....11 (5) 3. NUMERICAL SIMULATIONS OF IDENTICAL SYNCHRONIZATION To solve system of coupled differential equations (5)we were forced to use numerical simulation to obtain FME Transactions conclusions about possibilities of knots IS. We assume that horizontal and vertical directions of motion are independent, so for a general trajectory of knots motions we actually sum up the solutions from independent directions. For possible identical synchronization of vertical knots we are looking for the equality x3 t y3 t u3 t y9 t or x9 t v3 t u9 t v9 t and for possible synchronization x3 t y3 t x9 t v3 t or of the different forms of phase synchronization are possible and the synchronization attractor is visible. amplitude of excitation on main nod 33 A cos 33 t 3 2 4 6 7 8 5 5 6 6 7 xi coefficient of linear stiffness 11 2 5 33 3 1 4 2 6 7 8 11 11 n 4 4 4 coefficient of non linear stiffness frequence of excitation 10 5 atack angle on knot 33 atack angle on knot 93 5 10 ui n2,3 3 2 1 t1 u3 D cos n 2 , n 2t C cos n 2 ,3t atack angle on knot 39 atack angle on knot 99 n2,n2 5.......... ... n 4 n n 10 amplitude of excitation on main nod 33 u9 amplitude of excitation on main nod 93 10 amplitude of excitation on main nod 39 amplitude of excitation on main nod 99 5 2.08 2 Out[2]= n 4 B cos 6 y t 10 5 5 10 5 10 u3 atack angle on knot 33 atack angle on knot 93 6y coefficient of non linear stiffness frequence of excitation 3 4 atack angle on knot 39 D cos6vt 5 atack angle on knot 99 6v t1 10 D cos 99t ui 99 9 10 6x ... 9 5 10 ... 3 B cos 3, n 2t 3,n2 3 .......... ... coefficient of linear stiffness A cos6 xt 3 1 A cos 33 t 2 1 vi mi 3 0.45 1 4 8 93 3 2 vi mi 2 xi 10 7 C cos 93t 9 1 1 B cos39t 39 9 4 8 1 2 damping coefficient horizontal c i , c~i , bi yi 3 5 4 ui yi amplitude of excitation on main nod 99 knots u3 t y9 t u9 t v9 t and 1 2 33 3 1 vi mi 2 xi ci , ~ c i , bi damping coefficient ci , ~ c i , bi 1 10 amplitude of excitation on main nod 39 similar for the opposite combinations of knots. We also can provide different direction and position of the external excitation by changing the angle of attack on the particles ij and also position of the forces itself, Fig.2. yi u9 amplitude of excitation on main nod 93 10 11 C cos6ut ... 1 3 2 6u ... n 4 amplitude of excitation on main nod 33 u9 amplitude of excitation on main nod 93 n n 10 amplitude of excitation on main nod 39 amplitude of excitation on main nod 99 Figure 2. Crossed chains with knot external excitation or with excitation in the middle of the chains In the left part of the Fig.2 all four knots are attacked with external forces and we changed amplitudes and angles of attack like as values of coupling coefficients to synchronize them.The right part of the Fig. 2 presents possible attacks on the middles of the vertical chains, which perhaps give possibility of the diagonal symmetry of the lattice with synchrony of the opposite knots. We were looking for the diagonal x3 t y3 t u3 t y9 t for exploration of synchronization of nodes on first vertical chain (nodes 33 and 39). That was naturally possible in the completely symmetric lattice when external excitations perform for notes in the same manner. The nodes adjust the resulting movements and the synchronization attractor is visible after transition changes, Fig. 3. But for the value of the coefficient of linear coupling larger than 2.08, Fig. 3, middle part, the diagonal attractor is possible; the identical synchronisation is reached after some initial period of time called synchronization time. By increasing the damping coefficient the synchronisation time is smaller, the nodes are synchronised faster when the coupling is with greater damping coefficient. The following observation was IS of the opposite nodes 33 and 99, Fig.4, for the same case of symmetrically excited lattice. Synchronization of opposite nodes is less possible even though for larger values of coefficient of linear coupling, upper part of the Fig.4. But only increasing the damping coefficient the IS emerges even for the less values of the coupling strength, lower part of Fig. 4 the diagonal of synchronisation is visible. When lattice is not attacked symmetrically, for example when external excitation acts on nodes 33, 39 and 99, the IS is impossible, Fig.5. But after transition changes FME Transactions damping coefficient 5 1.405 coefficient of linear stiffness Out[3]= coefficient of non linear stiffness frequence of excitation 10 5 u3 atack angle on knot 33 atack angle on knot 93 atack angle on knot 39 5 atack angle on knot 99 t1 10 Figure 3. Synchronization attractors for knots from left vertical chain. External excitation acts on all four nodes. amplitude of excitation on main nod 33 node99 amplitude of excitation on main nod 93 15 amplitude of excitation on main nod 39 ci , ~ c i , bi yi amplitude of excitation on main nod 99 1 xi coefficient of linear stiffness 3 2 frequence of excitation 15 uatack angle on knot 33 n 5 4 10 5 C cos n 2,3t ui atack angle on knot 39 n2, 3 1 3 2 5 atack angle on knot 93 atack angle on knot 99 B cos 3, n 2t 3, n2 3 .......... ... 4 4 coefficient of non linear stiffness Out[5]= 1 2 33 3 1 10 A cos 33 t 2 damping coefficient vi mi 5 10 15 node33 D cos n 2, n 2t n 2 ,n 2 .......... ... n 4 10 t1 n n 15 amplitude of excitation on main nod 33 node99 amplitude of excitation on main nod 93 15 amplitude of excitation on main nod 39 amplitude of excitation on main nod 99 10 damping coefficient 1.215 5 coefficient of linear stiffness Out[6]= 2.08 coefficient of non linear stiffness 15 10 5 5 10 15 node33 frequence of excitation uatack angle on knot 33 5 atack angle on knot 93 atack angle on knot 39 10 atack angle on knot 99 t1 15 Figure 4. Synchronization attractors for opposite knots 33 and 99. External excitation acts on all four nodes. The upper part of Fig.5 presents phase synchronisation 3:1, and the lower part phase synchronisation 1:1. By increasing coefficient of linear coupling the possibilities of synchronization increase after transition process, middle part of the Fig.5. Increasing the frequency of excitations, the phase locking 1:1 of nodes gets better possibilities. VOL. 42, No 4, 2014 ▪ 343 amplitude of excitation on main nod 33 1 amplitude of excitation on main nod 39 33 3 2 1 1 A cos 33 t 3 damping coefficient vi 10 mi 2 xi amplitude of excitation on main nod 99 u9 ci , ~ c i , bi yi amplitude of excitation on main nod 93 2 3 .......... ... n 4 4 period of time lost IS, it is necessary that signal from external excitation from the middle of chain reachs to the node after some initial period and to disturb the synchrony. Increasing the time period we lost synchrony, Fig. 6 lower part. 4 5 0.26 coefficient of linear stiffness 0.535 In[2]:= coefficient of non linear stiffness 10 5 5 frequence of excitation 93 3 2 1 amplitude of excitation on central nod 61h n 4 6 amplitude of excitation on central nod 62h 5 ugao udara na cvor 93 u9 amplitude of excitation on central nod 61v 99 .......... ... ugao udara na cvor 33 u3 10 D cos 99t C cos 93t ui 0.17 amplitude of excitation on central nod 62v n n 4 damping coefficient ugao udara na cvor 39 coefficient of linear stiffness ugao udara na cvor 99 2 1.335 10 t1 In[12]:= coefficient of non linear stiffness frequence of excitation 6 4 2 2 4 u3 6 angle of attack on nod 61h 2 angle of attack on nod 61v angle of attack on nod 62h 4 angle of attack on nod 62v amplitude of excitation on main nod 33 u9 amplitude of excitation on main nod 93 t1 10 296 amplitude of excitation on main nod 39 6 amplitude of excitation on main nod 99 damping coefficient 5 Figure 7. Identical synchronization of nodes on first vertical chain (nodes 33 and 39). External excitations act on middle dots in vertical and horizontal chains 0.26 coefficient of linear stiffness 1.195 In[6]:= coefficient of non linear stiffness 10 5 5 u3 10 frequence of excitation 0.138 ugao udara na cvor 33 5 ugao udara na cvor 93 ugao udara na cvor 39 ugao udara na cvor 99 10 t1 amplitude of excitation on main nod 33 u9 amplitude of excitation on main nod 93 10 amplitude of excitation on main nod 39 amplitude of excitation on main nod 99 damping coefficient 5 coefficient of linear stiffness coefficient of non linear stiffness In[8]:= frequence of excitation 0.272 10 5 5 u3 10 ugao udara na cvor 33 ugao udara na cvor 93 ugao udara na cvor 39 5 ugao udara na cvor 99 t1 10 Figure 5. Synchronization attractors for knots from left vertical chain. External excitation acts on nodes 33; 93 and 99. amplitude of excitation on central nod 61h u9 amplitude of excitation on central nod 61v 6 c i , c~i , bi yi amplitude of excitation on central nod 62h 1 amplitude of excitation on central nod 62v 2 xi damping coefficient 1 3 n 4 4 4 2 coefficient of non linear stiffness In[9]:= 2 6x ... ... 3 2 1 A cos 6 x t 4 3 coefficient of linear stiffness vi mi By increasing coefficient of linear coupling the period of time in a synchrony of nodes is longer, Fig.7, we can notice that the period of time is the same like as on the lower part of Fig.6, but there is diagonal line representing IS because of the greater value of the coefficient of the linear coupling. When nodes from vertical chains share the signal from the external excitation that acts on the middle point of vertical chain, Fig. 8, then the initial identical synchronization is possible with transition to phase synchronization. If we retain all parameters on the same values and only change the position of the external excitations that acts on the middle points of the horizontal chains, Fig. 9, then we find out identical synchronisation of left vertical nodes. This is due to the fact that excitation is symmetric in the latter case, and in the first case the influence of the signal from the parallel chains that has time delay causes the transition to phase synchronization. amplitude of excitation on central nod 61h B cos6 y t frequence of excitation angle of attack on nod 61h 6 4 6 y 2 2 D cos6vt u9 amplitude of excitation on central nod 61v 6v 4 6 u3 6 amplitude of excitation on central nod 62h ci , ~ c i , bi yi 1 amplitude of excitation on central nod 62v angle of attack on nod 61v vi mi 2 ui angle of attack on nod 62v 6u ... ... 1 t1 3 2 4 damping coefficient C cos6ut 3 coefficient of linear stiffness n 4 n 3 n n 4 2 4 4 B cos 6 y t frequence of excitation ugao udara na cvor 61h 6 2 3 ... ... 2 1 coefficient of non linear stiffness In[13]:= 163. xi 6 4 2 D cos 6 v t 6 y 2 6v 4 u3 6 ugao udara na cvor 61v ugao udara na cvor 62h 2 ui ... ugao udara na cvor 62v 3 2 1 ... n 4 4 t1 n amplitude of excitation on central nod 61h 1 4 2 angle of attack on nod 62h n u9 amplitude of excitation on central nod 61v 6 6 amplitude of excitation on central nod 62h amplitude of excitation on central nod 62v 4 damping coefficient coefficient of linear stiffness 2 coefficient of non linear stiffness In[10]:= frequence of excitation angle of attack on nod 61h 6 4 2 2 4 6 u3 Figure 8. Identical synchronization of nodes on first vertical chain (nodes 33 and 39). External excitations act on middle dots in vertical chains angle of attack on nod 61v 2 angle of attack on nod 62h amplitude of excitation on central nod 61h angle of attack on nod 62v u9 amplitude of excitation on central nod 61v 4 t1 6 amplitude of excitation on central nod 62h 296 c i , c~i , bi yi 1 vi mi amplitude of excitation on central nod 62v 4 2 6 damping coefficient xi coefficient of linear stiffness 3 1 3 2 Figure 6. Synchronization of nodes on first vertical chain (nodes 33 and 39). External excitations act on middle dots in vertical and horizontal chains For the case when external excitations act on the middle of the chains like it was presented on the right part of Fig. 2, we have interesting phenomena of initial synchronization of knots, the diagonal line that is visible in the beginning of the motion, Fig. 6 upper part. In initial periods nodes are synchronize but after some 344 ▪ VOL. 42, No 4, 2014 Out[13]= frequence of excitation ugao udara na cvor 61h 2 3 n 4 2 4 coefficient of non linear stiffness 1 A cos 6 xt 6x ... ... 4 6 4 2 2 4 6 u3 ugao udara na cvor 61v ugao udara na cvor 62h ugao udara na cvor 62v 2 ui 6u ... ... 1 3 2 C cos 6u t n 4 4 t1 n n 6 Figure9. Identical synchronization of nodes on first vertical chain (nodes 33 and 39). External excitations act on middle dots in horizontal chains FME Transactions The presented numerical simulation was performed to the identical synchronization mostly of the nodes from the left vertical chain, but all the given conclusions have relevance to synchronization of the other nodes. 4. CONCLUSION The presented phenomenon of synchronization is very useful for elucidate the overall dynamics of large systems of material particles. The multi parametric computations (in silico) experiment is very useful tool for fast visual and parameter analysis of identical synchronization threshold. In chains with non-linear coupling the nonlinearity brings the properties of exponentially divergence of trajectories of particles that starts from very close points in phase space, nevertheless herein was shown that even in that systems one may find synchronization, which is rather surprising detail. The identical synchronisation of all four knots of the lattice is possible if every node is synchronized with the other three knots, furthermore it is possible to conclude about synchronization of all knots on the base of the three knots synchronization only if it the external excitations act on the symmetric position in the lattice. The possibilities for identical synchronisation are generally greater if the coefficients of coupling have greater values, but in some cases it is possible that we have ragged synchronization with increasing some parameters. On the base of these multi parametric numerical simulations it is easy to find out the needed and enough values of parameters for reaching IS, i.e. to find out synchronization threshold that varies with values of system parameter and with position and values of the external excitations. As it is shown, by measuring the synchronization times for different cases of excitations positions, that these simulations could be used for measure of signal processing in these models of chain lattices. ACKNOWLEDGMENT This research was sponsored by the research grant of the Serbian Ministry of Education, Science and Technological Development under the number ON 174001 REFERENCES [1] Pikovsky, A.; Rosemblum, M.; Kurths, J.: Synchronization: A Universal Concept in Nonlinear Sciences. Cambridge University Press, ISBN 0521-53352-X, 2001. [2] Fradkov A.L., Pogromsky A.Yu.: Introduction to control of oscillations and chaos. Singapore: World Scientific Publishers, 1998. [3] González-Miranda, J. M.: Synchronization and Control of Chaos. An introduction for scientists and FME Transactions engineers. Imperial College Press. ISBN 1-86094488-4, 2004. [4] Pecora, L.M., Carroll, T.L., Johnson, G.A., and Mar, D.J.: Fundamentals of Synchronization in Chaotic Systems, Concepts and Applications, Chaos, vol. 7, no. 4, pp. 520-543, 1997. [5] Balanov et al.: Synchronization: From Simple to Complex. Springer-Verlag, 2009. [6] Hedrih (Stevanović) K., Hedrih A.:Eigen modes of the double DNA chain helix vibrations , Journal of Theoretical and Applied Mechanics(JTAM),No. 1 (48),2010, p-p. 219-231, ISSN 1429-2955. [7] Hedrih A., Hedrih(Stevanovic) K., BugarskiB.: Oscillatory Spherical net model of Mouse ZonaPellucida. Journal of Applied Mathematics and bioinformatics. 2013, vol.3, no.4, 225-268., ISSN: 1792-6602, Scienpress Ltd, 2013. [8] Hedrih A.: Modelling oscillations of Zona Pellucida before and after fertilization. ENOC Young Scientist Prize, Paper. EUROMECH Newsletter 40, Dec. 2011, European Mechanics Society, 40, pp. 614. [9] Simonović J.: Synchronization in Coupled Systems with Different Type of Coupling Elements, Differntial Equations and Dynamical Systems, Volume 21, Issue 1 (2013), Pp. 141-148, © Springer 2013. [10] Hedrih K., Simonović J.: Non-linear dynamics of the sandwich double circular plate system, International Journal of Non-Linear Mechanics 45 (9),2010, p-p: 902-918. СИНХРОНИЗАЦИЈА У ЛАНЦИМА МАТЕРИЈАЛНИХ ТАЧАКА СА НЕЛИНЕАРНИМ СВОЈСТВИМА Јулијана Д. Симоновић Рад представља прелепе могућности идентичне синхронизације у динамици системима ланаца материјалних тачака. Спрежући елементи између материјалних тачака имају својства пригушења, линеарне и нелинеарне еластичнисти. Једна или више материјалних тачака ланца је периодички побуђена. Ефекат синхронизације је мање или више изражен зависно од својстава спрежучих елемената. Више параметарска анализа је извршена у фазном простору излазних променљивих спрегнутих материјалних тачака. Закључна разматрања садрже напомене о природи спрежућих елемената и симетрији у систему позиција дејства спољашње побуде које су потребне и довољне да би се достигао праг идентичне синхронизације. VOL. 42, No 4, 2014 ▪ 345
© Copyright 2026 Paperzz