A Study on Mathematical Modeling, Difference, Linear and Non-Linear Equations

Stability and Behavior of Differential Equations under Stochastic Perturbations

by Shashi Sharma*,

- Published in Journal of Advances and Scholarly Researches in Allied Education, E-ISSN: 2230-7540

Volume 15, Issue No. 4, Jun 2018, Pages 332 - 335 (4)

Published by: Ignited Minds Journals


ABSTRACT

We portray the worldwide asymptotic steadiness of the novel balance of a scalar deterministic customary differential equation when it is subjected to a stochastic annoyance free of the state. Another real undertaking is to order the asymptotic conduct of arrangements into concurrent, intermittent or limited under some more grounded mean returning condition on the nonlinearity. What is of uncommon intrigue is that, in the previous case, arrangements will be universally joined under the very same conditions on the force of the stochastic bother σ that apply in the straight case, and to be sure, these conditions which guarantee soundness are completely free of the kind of nonlinear mean inversion not at all like the deterministic case we don't have to make any presumption on the quality of the mean– inversion, simply that it is constantly present.

KEYWORD

mathematical modeling, difference, linear equations, non-linear equations, asymptotic stability, scalar, deterministic, ordinary differential equation, stochastic, nonlinearity

I. INTRODUCTION

1.1 Mathematical Modeling

Mathematical modeling is characterized as the interpretation of genuine problems into mathematical problems, figuring mathematical models vital for taking care of a problem and understanding of the results. It includes taking care of the mathematical problems and translating these solutions in the language of this present reality, approving the ends by contrasting them and the circumstance, and then either improving the model or, in the event that it is satisfactory, and applying the model to comparative circumstances for assessment and refinement. Stream graph for the procedure of mathematical model is given underneath:

Figure 1: Mathematical modeling Process Flow Chart

Mathematical modeling may likewise be characterized as the utilization of mathematics to portray and clarify real world marvels, research significant inquiries regarding the watched world, test thoughts and make expectations about the real world. There is no best model, just better models. It is utilized in regular sciences, for example, physics, science, and earth science, meteorology, engineering orders, for example, software engineering, man-made brainpower and in the social sciences, for example, economics, psychology, sociology and political theory. Mathematical modeling might be characterized by the mathematical techniques utilized in unraveling them, the reason we have for the model and as per their tendency: linear or non-linear, static or dynamic, deterministic or stochastic, discrete or ceaseless. Basically most realistic models are non-linear, dynamic and stochastic albeit linear, static or deterministic models are simpler to handle and likewise give great estimated results.

1.1.1 Mathematical Modeling Characteristics

 Hierarchy of models: Mathematical models are always improved to make them increasingly realistic. In this way for each circumstance, we get a hierarchy of models, every more realistic than the previous and each prone to be trailed by a superior one.  Realism of models: We need a mathematical model to be as realistic as would be prudent and to speak to reality as close as could be allowed. In any case, if a model is extremely realistic, it may not be mathematically tractable. In making a mathematical model, there must be an exchange off among tractability and reality. behavior of the model.  Relative precision of models: Different models vary in their precision and their concurrence with perceptions.  Overambitious and Oversimplified models: A model may not speak to reality since it is oversimplified. Then again, a model might be overambitious as in it might include such a large number of inconveniences and analysis of the results might be repetitive and unwieldy.  Self-consistency of models: A mathematical model includes conditions and inequations and these must be predictable. Here and there the inconsistency results from inconsistency of fundamental presumptions.  Models can prompt new experiments, new ideas and new mathematics: Comparison of predictions with perceptions uncovers the requirement for new experiments to gather required information. Mathematical models can prompt improvement of new ideas.  Complexity of models: This can be expanded by subdividing variables, by taking more variables and by thinking about more subtleties. Increment of complexity may not generally prompt increment of knowledge.  Models may prompt expected or unexpected predictions: Usually models give predictions expected on presence of mind contemplations, yet the model predictions are progressively quantitative in nature. Here and there they give unexpected predictions and may prompt developments, leaps forward or profound thought about presumptions. Now and then models give predictions totally at change with perceptions and these models should be updated definitely.  A model might be good, adequate, like reality for one reason and not for another: We need various models for clarifying various parts of a similar circumstance or notwithstanding for various scopes of the variables. Scan for a brought together model proceeds.  Modeling makes clear thinking: Before making a mathematical model, one must be clear about the structure and qualities of the circumstance. which can clarify, anticipate or control circumstances are satisfactory. A model may fit one circumstance great however might be a sad fit for another.

II. DIFFERENCE EQUATION

Difference equations are themselves as mathematical models portraying real life circumstances in science and innovation as well as in such different fields as economics, psychology, sociology and so on. In this way, difference equations are not the discrete analogs of differential equations in actuality they demonstrated the path for the improvement of the later. A few models from the various fields have been outlined, these are sufficient to pass on the significance of the qualitative just as quantitative investigation of difference equations. A nitty gritty investigation of difference equations with numerous references can be found. Without shut structure solutions to a large number of the linear and nonlinear difference equations a compensating elective is to be turned to the qualitative investigation of the solutions of the equations, for example, presence, uniqueness, wavering, soundness, and so on., without really building or approximating them. Interestingly with the differential equations, the presence and uniqueness of solutions of the underlying worth problems of the differential equations are ensured and subsequently we are keen on contemplating the other qualitative problems of the solutions of the difference equations. In the theory of difference equations, oscillatory and non-oscillatory solutions assume a significant job. A nontrivial arrangement of a difference equation is said to be oscillatory on the off chance that it is neither in the long run positive nor in the end negative. Else it is non-oscillatory. Albeit a few results in the discrete case are like those definitely known in the constant case isn't immediate yet requires some unique devices. Further, it was appeared there exists a few properties of differential equations which don't persist legitimately to the comparing difference equations.

III. LINEAR EQUATION

Since scalar direct SDEs have pulled in much consideration, in this area we clarify a portion of the similitudes and contrasts between our work and that which has showed up in the writing to date. We likewise rehash documentation, assistant capacities and procedures so as to state scalar variants of results from Chapter 2 that are important to the asymptotic investigation of the nonlinear equation. In this area, we talk about outcomes from the general asymptotic hypothesis of direct stochastic differential conditions. A valuable classification for arranging different classes of straight condition is given in Mao, for it comes to pass that the asymptotic conduct of conditions—and the comparing examination of their asymptotic conduct—contrasts over these classifications. As we center in this area around scalar conditions, we restrict consideration currently to the most broad scalar straight condition. We say that the scalar procedure X is an answer of a direct stochastic differential condition on the off chance that it complies. where r ≥ 1 is an integer, aj and fj for j = 0, . . . , r are appropriately regular functions, and B = (B1, . . . , Br) is a r– dimensional standard Brownian movement. To improve our discourse, we accept the coherence of the f's and a's, which is adequate to guarantee the presence of a remarkable solid arrangement of (1). The condition (1) is named homogeneous if fj (t) ≡ 0 for all t ≥ 0 and all j = 0. . . r. For such a condition, if X(0) = 0, at that point the remarkable arrangement is X(t) = 0 for all t ≥ 0 a.s., so the nearness of the stochastic terms protects the zero balance of the basic deterministic differential condition A to a great degree far reaching hypothesis concerning the security of the zero arrangement of (1) exists for homogeneous conditions, and is elucidated in e.g., Khas'minski, to which we insinuate by and by. For some other non– homogeneous condition, X(0) = 0 does not infer that X(t) = 0 for all t ≥ 0, and it is now and again said that the non– self-governing annoyances fj are not equilibrium– safeguarding. For example, if aj (t) ≡ 0 for all t ≥ 0 and j = 1. . . r, the dispersion coefficient depends just on t (and is along these lines state– free) and the condition is named direct in the restricted sense. These conditions are in some sense the least complex in the class of direct conditions, as their answers can be communicated unequivocally as far as the essential arrangement of (2).

IV. NONLINEAR EQUATION

In this area we investigate the asymptotic conduct of the nonlinear differential condition. In the initial segment of this segment, we build up an association between the arrangements of (1). This empowers us to express the primary consequences of the section, which show up, together with translation and examples, in the second piece of this area. A general arrangement solution for nonlinear differential equations dependent on a substitute type of the underlying estimate to the precise solution and an auxiliary parameter to guarantee combination of the arrangement solution. The general arrangement solution straightforwardly from the zero-order deformation equation as far as the polynomial and acquaint another measurement with the combination attributes during a time auxiliary parameter. Comparison of the present and accurate solutions affirms the viability and legitimacy of the proposed methodology. The utilization of the auxiliary parameters substantially improves the intermingling area and rate and gives arrangement solutions to exceptionally nonlinear equations with less terms. Convergence hypotheses are given to guarantee wide use of the general solution to nonlinear differential equations. We show the execution of the general arrangement solution in physical science problems including the linear and nonlinear allegorical equation. Their nonlinear qualities and precise solutions permit examination and check of the proposed method. The traditional homotopy analysis method has given analytical solutions to the nonlinear equation, to constrained assembly attributes. This shows the upsides of the proposed method with unequivocally nonlinear problems. Non-linear system of explanatory differential equations: emerge in different parts of sciences and engineering, for example, liquid dynamics, heat flow, dissemination, flexible vibration and so forth. Here ∇2 indicates the Laplacian operator and f and) (u, v) g(u, v are non-linear function of u and v.

V. CONCLUSION

Numerical analysis in mathematics intends to tackle mathematical problems by arithmetic operations: addition, subtraction, multiplication, division and comparison. Since these operations are actually those that PCs can do, numerical analysis and PCs are personally related. With the advancement of quick, proficient computerized PCs, the job of numerical methods in taking care of logical and engineering problems has expanded significantly in present day time years. The advancement of numerous marvels in nature is depicted by differential and difference equations. Amid the previous four decades or somewhere in the vicinity, surprising advancement has been made in understanding the integrable properties of some partial differential equations (PDE). The mathematical theory of non-linear wave equations

REFERENCES

1. Abbasbandy, S. (2003). Improving Newton-Raphson method for nonlinear equations by modified Adomian decomposition method. Appl. Math. Comput. 145: pp. 887–893 2. Amat, S., Busquier, S. and Guitierrez, J.M. (2003). Geometric constructions of itera- ´ tive functions to solve nonlinear equations. J. Comput. Appl. Math. 157: pp. 197–205 3. Babajee, D.K.R., Dauhoo, M.Z., Darvishi, M.T., Karami, A. and Barati, A. (2010). Analysis of two Chebyshev-like third order methods free from second derivatives for solving systems of nonlinear equations. J. Comput. Appl. Math. 233: pp. 2002–2012 4. Bi, W., Ren, H. and Wu, Q. (2009). Three-step iterative methods with eighth-order convergence for solving nonlinear equations. J. Comput. Appl. Math. 225: pp. 105–112 5. Biazar, J. and Ghanbari, B. (2010). A new third-order family of nonlinear solvers for multiple roots. Comput. Math. Appl. 59: pp. 3315–3319 6. Chun, C. (2007). A geometric construction of iterative functions of order three to solve nonlinear equations. Comp. Math. Appl. 53: pp. 972–976 7. Chun, C. (2007). A one-parameter family of third-order methods to solve nonlinear equations. Appl. Math. Comput. 189: pp. 126–130 8. Chun, C. (2010). A geometric construction of itertive formulas of order three. Appl. Math. Lett. 23: pp. 512–516 9. Cordero, A., Hueso, J,L., Mart´inez, E. and Torregrosa, J.R. (2010). A family of iterative methods with sixth and seventh order convergence for nonlinear equations. Math. Comput. Modell. 52: pp. 1490–1496 10. Cordero, A., Hueso, J.L., Mart´inez, E. and Torregrosa, J.R. (2010). New modifications of Potra-Ptak‘s method with optimal fourth and eighth orders of convergence. ´ J. Comput. Appl. Math. 234: pp. 2969–2976

Shashi Sharma*

Mathematics Department, DAV College, Muzaffarnagar-251001