scholarly journals Direct coupling: a possible strategy to control fruit production in alternate bearing

2017 ◽  
Vol 7 (1) ◽  
Author(s):  
Awadhesh Prasad ◽  
Kenshi Sakai ◽  
Yoshinobu Hoshino
Keyword(s):  
Phase Synchronization ◽  
Initial Conditions ◽  
Fruit Production ◽  
Direct Coupling ◽  
Alternate Bearing ◽  
Tent Map ◽  
Coupled Nonlinear Oscillators ◽  
Resource Budget Model ◽  
Field Experimentation ◽  
The Given

Abstract We investigated the theoretical possibility of applying phenomenon of synchronization of coupled nonlinear oscillators to control alternate bearing in citrus. The alternate bearing of fruit crops is a phenomenon in which a year of heavy yield is followed by an extremely light one. This phenomenon has been modeled previously by the resource budget model, which describes a typical nonlinear oscillator of the tent map type. We have demonstrated how direct coupling, which could be practically realized through grafting, contributes to the nonlinear dynamics of alternate bearing, especially phase synchronization. Our results show enhancement of out-of-phase synchronization in production, which depends on initial conditions obtained under the given system parameters. Based on these numerical experiments, we propose a new method to control alternate bearing, say in citrus, thereby enabling stable fruit production. The feasibility of validating the current results through field experimentation is also discussed.

scholarly journals Spatial Phase Synchronisation of Pistachio Alternate Bearing

2021 ◽  
Author(s):  
Kenshi Sakai ◽  
Patrick Brown ◽  
Todd Rosenstock ◽  
Shrinivasa Upadhyaya ◽  
Alan Hastings
Keyword(s):  
Spatial Synchrony ◽  
Alternate Bearing ◽  
Tent Map ◽  
Perennial Plant ◽  
Common Noise ◽  
Analysis Technique ◽  
Efficient Resource ◽  
Great Relevance ◽  
Resource Budget Model ◽  
Phase Out

Abstract Nonlinear physics and agroecosystems can be of great relevance in the synchronisations of chaotic oscillators. The endogenous dynamics of the seed production of perennial plant species which include alternate bearing and masting, portray typical synchronisation patterns in nature and can be modelled using a tent map known as a resource budget model (RBM). This study investigates the collective rhythm in 9,562 pistachio trees caused by their endogenous network dynamics and exogenous forces (common noise). Common noise and a local coupling of RBMs are the two primary factors emerging from the bearing phase synchronisation in this orchard. The in-phase/out-of-phase analysis technique quantifying the strength of the phase synchronisation in trees (population /individual) allows us to study the observed spatial synchrony in detail. We demonstrate how three essential factors, i.e. (a) common noise, (b) local direct coupling, and (c) the gradient of the cropping coefficient, explain the spatial synchrony of the orchard. Here, we also show that the methodology employing nonlinear physics to study agroecological systems can be useful for resolving practical problems in agriculture including yield variability and spatial synchrony which often compromise efficient resource management.

scholarly journals A Mathematical Model for Nipah Virus Infection

2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Assefa Denekew Zewdie ◽  
Sunita Gakkhar
Keyword(s):  
Virus Infection ◽  
Reproduction Number ◽  
Initial Conditions ◽  
Nipah Virus ◽  
Virus Transmission ◽  
Globally Asymptotically Stable ◽  
Dead Bodies ◽  
Manifold Theory ◽  
The Impact ◽  
The Given

It has been reported that unprotected contact with the dead bodies of infected individuals is a plausible way of Nipah virus transmission. An SIRD model is proposed in this paper to investigate the impact of unprotected contact with dead bodies of infected individuals before burial or cremation and their disposal rate on the dynamics of Nipah virus infection. The model is analyzed, and the reproduction number is computed. It is established that the disease-free state is globally asymptotically stable when the reproduction number is less than unity and unstable if it is greater than unity. By using the central manifold theory, we observe that the endemic equilibrium is locally stable near to unity. It is concluded that minimizing unsafe contact with the infected dead body and/or burial or cremation as fast as possible contributes positively. Further, the numerical simulations for the given choice of data and initial conditions illustrate that the endemic state is stable and the disease persists in the community when the reproduction number is greater than one.

scholarly journals A New Approach for Solving the Undamped Helmholtz Oscillator for the Given Arbitrary Initial Conditions and Its Physical Applications

2020 ◽  
Vol 2020 ◽  
pp. 1-7
Author(s):  
Alvaro H. Salas S ◽  
Jairo E. Castillo H ◽  
Darin J. Mosquera P
Keyword(s):  
Differential Equation ◽  
Approximate Solution ◽  
Analytical Solution ◽  
Initial Conditions ◽  
Negative Ions ◽  
Nonlinear Problems ◽  
New Approach ◽  
Weierstrass Elliptic Function ◽  
Electronegative Plasma ◽  
The Given

In this paper, a new analytical solution to the undamped Helmholtz oscillator equation in terms of the Weierstrass elliptic function is reported. The solution is given for any arbitrary initial conditions. A comparison between our new solution and the numerical approximate solution using the Range Kutta approach is performed. We think that the methodology employed here may be useful in the study of several nonlinear problems described by a differential equation of the form z ″ = F z in the sense that z = z t . In this context, our solutions are applied to some physical applications such as the signal that can propagate in the LC series circuits. Also, these solutions were used to describe and investigate some oscillations in plasma physics such as oscillations in electronegative plasma with Maxwellian electrons and negative ions.

UNCERTAINTY IN CHAOS SYNCHRONIZATION

2001 ◽  
Vol 11 (06) ◽  
pp. 1723-1735 ◽  
Author(s):  
GUO-QUN ZHONG ◽  
KIM-FUNG MAN ◽  
KING-TIM KO
Keyword(s):  
Coupling Strength ◽  
Chaos Synchronization ◽  
Phase Synchronization ◽  
Initial Conditions ◽  
Coupled Systems ◽  
Sensitive Dependence ◽  
Initial States ◽  
Synchronization Regime

In this paper a variety of uncertainty phenomena in chaos synchronization, which are caused by the sensitive dependence on initial conditions and coupling strength, are numerically investigated. Two identical Chua's circuits are considered for both mutually- and unidirectionally-coupled systems. It is found that initial states of the system play an important role in chaos synchronization. Depending on initial conditions, distinct behaviors, such as in-phase synchronization, anti-phase synchronization, oscillation-quenching, and bubbling of attractors, may occur. Based on the findings, we clarify that the systems, which satisfy the standard synchronization criterion, do not necessarily operate in a synchronization regime.

Learning solutions to the source inverse problem of wave equations using LS-SVM

2019 ◽  
Vol 27 (5) ◽  
pp. 657-669 ◽  
Author(s):  
Ziku Wu ◽  
Chang Ding ◽  
Guofeng Li ◽  
Xiaoming Han ◽  
Juan Li
Keyword(s):  
Inverse Problem ◽  
Approximate Solution ◽  
Support Vector Machines ◽  
Wave Equations ◽  
Source Term ◽  
Initial Conditions ◽  
Support Vector ◽  
Vector Machines ◽  
Robustness To Noise ◽  
The Given

Abstract A method based on least squares support vector machines (LS-SVM) is proposed to solve the source inverse problem of wave equations. Contrary to the most existing methods, the proposed method provides a closed form approximate solution which satisfies the boundary conditions and the initial conditions. The proposed method can recover the unknown source term with the given additional conditions. Furthermore, it has reasonable robustness to noise. Numerical results show the proposed method can be used to solve the source inverse problem of wave equations.

SYNCHRONIZING CHAOTIC ATTRACTORS OF CHUA'S CANONICAL CIRCUIT: THE CASE OF UNCERTAINTY IN CHAOS SYNCHRONIZATION

2006 ◽  
Vol 16 (07) ◽  
pp. 1961-1976 ◽  
Author(s):  
I. M. KYPRIANIDIS ◽  
A. N. BOGIATZI ◽  
M. PAPADOPOULOU ◽  
I. N. STOUBOULOS ◽  
G. N. BOGIATZIS ◽  
...  
Keyword(s):  
Coupling Strength ◽  
Chaos Synchronization ◽  
Phase Synchronization ◽  
Initial Conditions ◽  
Chaotic Synchronization ◽  
Chaotic Attractors ◽  
Coexisting Attractors

In this paper, we have studied the dynamics of two identical resistively coupled Chua's canonical circuits and have found that it is strongly affected by initial conditions, coupling strength and the presence of coexisting attractors. Depending on the coupling variable, chaotic synchronization has been observed both numerically and experimentally. Anti-phase synchronization has also been studied numerically clarifying some aspects of uncertainty in chaos synchronization.

Influence of the Longitudinal Excavations Layout on Stress Concentration Value in the Peripheral Rock Mass

2014 ◽  
Vol 682 ◽  
pp. 196-201 ◽  
Author(s):  
Alexander F. Revuzhenko ◽  
Anton A. Kazantsev ◽  
Yuri F. Glazkov ◽  
Andrey A. Dortman
Keyword(s):  
Rock Mass ◽  
Stress Concentration ◽  
Computational Model ◽  
Initial Conditions ◽  
Reaction Forces ◽  
The Given

The article proposes an analysis of the various longitudinal excavations layouts in tunnel walls. The excavations are required for taking reaction forces when a ‘geokhod’ works. A computational model of the peripheral rock mass is presented. Calculations showed that the X-type layout of the longitudinal excavations is most acceptable for the given initial conditions.

On the dynamics of the Tent function - Phase diagrams

2016 ◽  
Vol 7 (4) ◽  
pp. 261
Author(s):  
Prince Amponsah Kwabi ◽  
William Obeng Denteh ◽  
Richard Kena Boadi
Keyword(s):  
Dynamical Systems ◽  
Phase Diagrams ◽  
Initial Conditions ◽  
Asymptotic Properties ◽  
Topological Dynamical System ◽  
Topological Transitivity ◽  
Tent Map ◽  
One Dimensional ◽  
Definition Of ◽  
Topological Dynamical Systems

This paper focuses on the study of a one-dimensional topological dynamical system, the tent function. We give a good background to the theory of dynamical systems while establishing the important asymptotic properties of topological dynamical systems that distinguishes it from other fields by way of an example - the tent function. A precise definition of the tent function is given and iterates are clearly shown using the phase diagrams. By this same method, chaos in the tent map is shown as iterates become higher. We also show that the tent map has infinitely many chaotic orbits and also express some important features of chaos such as topological transitivity, boundedness and sensitivity to change in initial conditions from a topological viewpoint.

MULTIPLE OSCILLATORY STATES IN MODELS OF COLLECTIVE NEURONAL DYNAMICS

2014 ◽  
Vol 24 (06) ◽  
pp. 1450020 ◽  
Author(s):  
STILIYAN KALITZIN ◽  
MARCUS KOPPERT ◽  
GEORGE PETKOV ◽  
FERNANDO LOPES DA SILVA
Keyword(s):  
Analytical Model ◽  
Large Scale ◽  
Computational Models ◽  
Phase Synchronization ◽  
Initial Conditions ◽  
State Transitions ◽  
Model Parameters ◽  
Reactive Control ◽  
Stable States ◽  
Optimal Method

In our previous studies, we showed that the both realistic and analytical computational models of neural dynamics can display multiple sustained states (attractors) for the same values of model parameters. Some of these states can represent normal activity while other, of oscillatory nature, may represent epileptic types of activity. We also showed that a simplified, analytical model can mimic this type of behavior and can be used instead of the realistic model for large scale simulations. The primary objective of the present work is to further explore the phenomenon of multiple stable states, co-existing in the same operational model, or phase space, in systems consisting of large number of interconnected basic units. As a second goal, we aim to specify the optimal method for state control of the system based on inducing state transitions using appropriate external stimulus. We use here interconnected model units that represent the behavior of neuronal populations as an effective dynamic system. The model unit is an analytical model (S. Kalitzin et al., Epilepsy Behav. 22 (2011) S102–S109) and does not correspond directly to realistic neuronal processes (excitatory–inhibitory synaptic interactions, action potential generation). For certain parameter choices however it displays bistable dynamics imitating the behavior of realistic neural mass models. To analyze the collective behavior of the system we applied phase synchronization analysis (PSA), principal component analysis (PCA) and stability analysis using Lyapunov exponent (LE) estimation. We obtained a large variety of stable states with different dynamic characteristics, oscillatory modes and phase relations between the units. These states can be initiated by appropriate initial conditions; transitions between them can be induced stochastically by fluctuating variables (noise) or by specific inputs. We propose a method for optimal reactive control, allowing forced transitions from one state (attractor) into another.

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