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The aim of the paper is to give a theorem about the existence and uniqueness of a solution of a nonlocal Cauchy problem for an ordinary differential equation in a … The aim of the paper is to give a theorem about the existence and uniqueness of a solution of a nonlocal Cauchy problem for an ordinary differential equation in a Banach space. The Banach theorem about the fixed point is used to prove the existence and uniqueness of a solution of the problem considered. The result obtained in this paper can be applied among other things to the description of motion phenomena with better effect than the classical Cauchy problem.
Fuzzy differential functions are applicable to real-world problems in engineering, computer science, and social science. That relevance makes for rapid development of new ideas and theories. This volume is a … Fuzzy differential functions are applicable to real-world problems in engineering, computer science, and social science. That relevance makes for rapid development of new ideas and theories. This volume is a timely introduction to the subject that describes the current state of the theory of fuzzy differential equations and inclusions and provides a systematic account of recent developments. The chapters are presented in a clear and logical way and include the preliminary material for fuzzy set theory; a description of calculus for fuzzy functions, an investigation of the basic theory of fuzzy differential equations, and an introduction to fuzzy differential inclusions.
Provides a clear and comprehensive overview of the fundamental theories, numerical methods, and iterative processes encountered in difference calculus. Explores classical problems such as orthological polynomials, the Euclidean algorithm, roots … Provides a clear and comprehensive overview of the fundamental theories, numerical methods, and iterative processes encountered in difference calculus. Explores classical problems such as orthological polynomials, the Euclidean algorithm, roots of polynomials, and well-conditioning.
""Providing the theoretical framework to model phenomena with discontinuous changes, this unique reference presents a generalized monotone iterative method in terms of upper and lower solutions appropriate for the study … ""Providing the theoretical framework to model phenomena with discontinuous changes, this unique reference presents a generalized monotone iterative method in terms of upper and lower solutions appropriate for the study of discontinuous nonlinear differential equations and applies this method to derive suitable fixed point theorems in ordered abstract spaces.
First order differential equations first order differential systems higher order differential equations differential equations in abstract spaces complex differential equations functional differential equations impulsive differential equations differential equations with hysteresis … First order differential equations first order differential systems higher order differential equations differential equations in abstract spaces complex differential equations functional differential equations impulsive differential equations differential equations with hysteresis generalized differential equations.
A basic feedback control problem is that of obtaining some desired stability property from a system which contains uncertainties due to unknown inputs into the system. Despite such imperfect knowledge … A basic feedback control problem is that of obtaining some desired stability property from a system which contains uncertainties due to unknown inputs into the system. Despite such imperfect knowledge in the selected mathematical model, we often seek to devise controllers that will steer the system in a certain required fashion. Various classes of controllers whose design is based on the method of Lyapunov are known for both discrete [4], [10], [15], and continuous [3–9], [11] models described by difference and differential equations, respectively. Recently, a theory for what is known as dynamic systems on time scales has been built which incorporates both continuous and discrete times, namely, time as an arbitrary closed sets of reals, and allows us to handle both systems simultaneously [1], [2], [12], [13]. This theory permits one to get some insight into and better understanding of the subtle differences between discrete and continuous systems. We shall, in this paper, utilize the framework of the theory of dynamic systems on time scales to investigate the stability properties of conditionally invariant sets which are then applied to discuss controlled systems with uncertain elements. For the notion of conditionally invariant set and its stability properties, see [14]. Our results offer a new approach to the problem in question.
In this paper, we develop the theory of fractional dieren tial inequalities involving Riemann-Loiuville dieren tial operators of order 0 < q < 1, use it for the existence of … In this paper, we develop the theory of fractional dieren tial inequalities involving Riemann-Loiuville dieren tial operators of order 0 < q < 1, use it for the existence of extremal solutions and global existence. Necessary tools are discussed and the comparison principle is proved which will be useful for further study of qualitative behavior of solutions.
AMS (MOS) subject classification (1970): Primary 34K15; Secondary 34K25, 34E10. A sufficient condition under which all solutions of the delay differential equation , where p(t≤0 and continuous and τ>0 and … AMS (MOS) subject classification (1970): Primary 34K15; Secondary 34K25, 34E10. A sufficient condition under which all solutions of the delay differential equation , where p(t≤0 and continuous and τ>0 and constant, are oscillatory is presented. It is explained that the condition is the best possible for oscillations. When the coefficient p(t) in equation (1) is a positive constant, p, then the condition becomes pτe>0 which is necessary and sufficient for all solutions of the DDE to be oscillatory.
In this paper, the basic theory of fractional differential equations in a Banach Space is discussed including flow invariance and theory of inequalities in cones. In this paper, the basic theory of fractional differential equations in a Banach Space is discussed including flow invariance and theory of inequalities in cones.
Abstract Abstract Let (X, ≤) be a partially ordered set and suppose there is a metric d on X such that (X, d) is a complete separable metric space and … Abstract Abstract Let (X, ≤) be a partially ordered set and suppose there is a metric d on X such that (X, d) is a complete separable metric space and (Ω, Σ) be a measurable space. In this article a pair of random mappings F: Ω × (X × X) → X and g: Ω × X → X, where F has a mixed g-monotone property on X, and F and g satisfy the non-linear contractive condition (5) below, are introduced and investigated. Two coupled random coincidence and coupled random fixed point theorems are proved. These results are random versions and extensions of recent results of Lakshmikantham and Ćirić [V. Lakshmikantham and Lj. Ćirić, Coupled fixed point theorems for nonlinear contractions in partially ordered metric spaces. Nonlinear Anal.—Theor. 70(12) (2009): 4341–4349] and include several recent developments. Keywords: Coupled coincidenceCoupled fixed pointMeasurable mappingMixed monotone mappingRandom operatorMathematics Subject Classification: Primary 47H10Secondary 54H25, 34B15
In this paper the theory of fixed point theorems of nonlinear whose domain and range are different Banach spaces are considered. Also the analogues of the Contraction Mapping Principle. Krasnoselskii's … In this paper the theory of fixed point theorems of nonlinear whose domain and range are different Banach spaces are considered. Also the analogues of the Contraction Mapping Principle. Krasnoselskii's fixed point theorem and a result on the convergence of quasinonexpansive mappings are dealt with. As an application, the existence and uniqueness of solutions of differential equations with retarded argument in Banach spaces are discussed
In this paper, we discuss the existence of extremal solutions for impulsive differential equations (IDE) with variable times using a new approach, develop the necessary comparison result parallel to the … In this paper, we discuss the existence of extremal solutions for impulsive differential equations (IDE) with variable times using a new approach, develop the necessary comparison result parallel to the one in ODE and apply it for the investigation of stability criteria. In the context of stability investigation, it is natural to consider the existence of a solution that meets each given barrier (hypersurface) exactly once i.e., the lack of pulse phenomenon. With this motivation, we also consider a result on existence of solutions which meet the given hypersurfaces only once and this result is a refinement of the known result in [5]. We do hope that the new idea of this paper will be of value in the study of qualitative behavior of solutions of IDE with variable times whose progress so far has been slow.
""Providing the theoretical framework to model phenomena with discontinuous changes, this unique reference presents a generalized monotone iterative method in terms of upper and lower solutions appropriate for the study … ""Providing the theoretical framework to model phenomena with discontinuous changes, this unique reference presents a generalized monotone iterative method in terms of upper and lower solutions appropriate for the study of discontinuous nonlinear differential equations and applies this method to derive suitable fixed point theorems in ordered abstract spaces.
A unified approach for the monotone iterative technique is discussed for the nonlinear elliptic boundary value problems when the nonlinear right-hand side is the sum of two monotone functions. This … A unified approach for the monotone iterative technique is discussed for the nonlinear elliptic boundary value problems when the nonlinear right-hand side is the sum of two monotone functions. This setting includes several results and can be applied to other nonlinear problems.
In this chapter we stress the importance of nonlinear variation of parameters formulae for a variety of nonlinear problems as well as monotone iterative technique that offers constructive methods for … In this chapter we stress the importance of nonlinear variation of parameters formulae for a variety of nonlinear problems as well as monotone iterative technique that offers constructive methods for the existence of solution in a sector.
In this chapter, stability considerations are extended to a variety of nonlinear systems utilizing the same versatile tools, namely, Lyapunov-like functions, theory of appropriate inequalities and different measures, that were … In this chapter, stability considerations are extended to a variety of nonlinear systems utilizing the same versatile tools, namely, Lyapunov-like functions, theory of appropriate inequalities and different measures, that were developed in the previous chapters. In order to avoid monotony, we have restricted ourselves to present only typical extensions which demonstrate the essential unity achieved and pave the way for further work.
Asymptotic Methods in Resonance Analytical Dynamics presents new asymptotic methods for the analysis and construction of solutions (mainly periodic and quasiperiodic) of differential equations with small parameters. Along with some … Asymptotic Methods in Resonance Analytical Dynamics presents new asymptotic methods for the analysis and construction of solutions (mainly periodic and quasiperiodic) of differential equations with small parameters. Along with some background material and theory behind these methods, the authors also consider a variety of problems and applications in nonlinear mechanics and oscillation theory. The methods examined are based on two types: the generalized averaging technique of Krylov-Bogolubov and the numeric-analytical iterations of Lyapunov-Poincaré. This text provides a useful source of reference for postgraduates and researchers working in this area of applied mathematics.
Abstract Abstract Let (X, ≤) be a partially ordered set and suppose there is a metric d on X such that (X, d) is a complete separable metric space and … Abstract Abstract Let (X, ≤) be a partially ordered set and suppose there is a metric d on X such that (X, d) is a complete separable metric space and (Ω, Σ) be a measurable space. In this article a pair of random mappings F: Ω × (X × X) → X and g: Ω × X → X, where F has a mixed g-monotone property on X, and F and g satisfy the non-linear contractive condition (5) below, are introduced and investigated. Two coupled random coincidence and coupled random fixed point theorems are proved. These results are random versions and extensions of recent results of Lakshmikantham and Ćirić [V. Lakshmikantham and Lj. Ćirić, Coupled fixed point theorems for nonlinear contractions in partially ordered metric spaces. Nonlinear Anal.—Theor. 70(12) (2009): 4341–4349] and include several recent developments. Keywords: Coupled coincidenceCoupled fixed pointMeasurable mappingMixed monotone mappingRandom operatorMathematics Subject Classification: Primary 47H10Secondary 54H25, 34B15
This chapter deals with extensions and generalizations of causal differential equations to other important areas of nonlinear analysis. We begin with the set differential equations with causal operators naming them … This chapter deals with extensions and generalizations of causal differential equations to other important areas of nonlinear analysis. We begin with the set differential equations with causal operators naming them as causal set differential equations (CSDE). Set differential equations in a metric space has gained much attention recently due to its applicability to multivalued differential inclusions and fuzzy differential equations and its inclusion of ordinary differential systems as a special case. The generalization of this dynamic system to include causal differential equations would cover a wider variety of situations and therefore, it would initiate an interesting and useful branch of nonlinear analysis that requires further investigation.
In this paper an attempt is made to prove some mean value theorems for fractional differential equations. Further, a new function, called Ultra Mittag Leffler function is introduced which was … In this paper an attempt is made to prove some mean value theorems for fractional differential equations. Further, a new function, called Ultra Mittag Leffler function is introduced which was the outcome of proving existence and uniqueness result using successive approximations under Holder condition for fractional differential function.
Recently fractional differential equations involving Riemann‐Loiuville type as well as Caputo type has gained importance due to its application. In this paper we compare and contrast these two types of … Recently fractional differential equations involving Riemann‐Loiuville type as well as Caputo type has gained importance due to its application. In this paper we compare and contrast these two types of equations and present the latest development relative to them.
It is known that a Fréchet space 𝔽 can be realized as a projective limit of a sequence of Banach spaces . The space Kc(𝔽) of all compact, convex subsets … It is known that a Fréchet space 𝔽 can be realized as a projective limit of a sequence of Banach spaces . The space Kc(𝔽) of all compact, convex subsets of a Fréchet space, 𝔽, is realized as a projective limit of the semilinear metric spaces . Using the notion of Hukuhara derivative for maps with values in Kc(𝔽), we prove the local and global existence theorems for an initial value problem associated with a set differential equation.
In this paper, the basic theory of fractional differential equations in a Banach Space is discussed including flow invariance and theory of inequalities in cones. In this paper, the basic theory of fractional differential equations in a Banach Space is discussed including flow invariance and theory of inequalities in cones.
Using the notion of continuous approximate selec- tions, we establish an existence theorem for set differential inclusions in a semi-linear metric space. Using the notion of continuous approximate selec- tions, we establish an existence theorem for set differential inclusions in a semi-linear metric space.
Recently it is proposed that the behavior of the solutions of fuzzy dieren tial equa- tions (FDEs) could be tamed by a suitable forcing term. In this context a case … Recently it is proposed that the behavior of the solutions of fuzzy dieren tial equa- tions (FDEs) could be tamed by a suitable forcing term. In this context a case has been made that FDEs need to be investigated as a separate discipline instead of treating them as fuzzy analogues of crisp counterparts. Here in this paper, we support this argument also by showing how dieren t formulations of a fuzzy dieren tial equation can lead to solutions with dieren t behaviors, adding richness to the theory of FDEs. For this aim we use the notions of Hukuhara dieren tial, generalized dieren tiability, dieren tial inclusions and the interpretation of FDEs by using Zadeh's extension principle on the classical solution. We also point out several possible research directions in the study of FDEs.
In this paper, we develop the theory of fractional dieren tial inequalities involving Riemann-Loiuville dieren tial operators of order 0 < q < 1, use it for the existence of … In this paper, we develop the theory of fractional dieren tial inequalities involving Riemann-Loiuville dieren tial operators of order 0 < q < 1, use it for the existence of extremal solutions and global existence. Necessary tools are discussed and the comparison principle is proved which will be useful for further study of qualitative behavior of solutions.
New existence results are presented for fuzzy differential and integral equations. Our analysis combines the stacking theorem with results concerning the maximal solution for an appropriate differential equation. New existence results are presented for fuzzy differential and integral equations. Our analysis combines the stacking theorem with results concerning the maximal solution for an appropriate differential equation.
Fuzzy differential functions are applicable to real-world problems in engineering, computer science, and social science. That relevance makes for rapid development of new ideas and theories. This volume is a … Fuzzy differential functions are applicable to real-world problems in engineering, computer science, and social science. That relevance makes for rapid development of new ideas and theories. This volume is a timely introduction to the subject that describes the current state of the theory of fuzzy differential equations and inclusions and provides a systematic account of recent developments. The chapters are presented in a clear and logical way and include the preliminary material for fuzzy set theory; a description of calculus for fuzzy functions, an investigation of the basic theory of fuzzy differential equations, and an introduction to fuzzy differential inclusions.
Fuzzy differential functions are applicable to real-world problems in engineering, computer science, and social science. That relevance makes for rapid development of new ideas and theories. This volume is a … Fuzzy differential functions are applicable to real-world problems in engineering, computer science, and social science. That relevance makes for rapid development of new ideas and theories. This volume is a timely introduction to the subject that describes the current state of the theory of fuzzy differential equations and inclusions and provides a systematic account of recent developments. The chapters are presented in a clear and logical way and include the preliminary material for fuzzy set theory; a description of calculus for fuzzy functions, an investigation of the basic theory of fuzzy differential equations, and an introduction to fuzzy differential inclusions.
""Providing the theoretical framework to model phenomena with discontinuous changes, this unique reference presents a generalized monotone iterative method in terms of upper and lower solutions appropriate for the study … ""Providing the theoretical framework to model phenomena with discontinuous changes, this unique reference presents a generalized monotone iterative method in terms of upper and lower solutions appropriate for the study of discontinuous nonlinear differential equations and applies this method to derive suitable fixed point theorems in ordered abstract spaces.
In this paper the problem of existence of solutions to the initial value problem <inline-formula content-type="math/mathml"> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="u prime left-parenthesis t right-parenthesis equals upper A left-parenthesis t comma u … In this paper the problem of existence of solutions to the initial value problem <inline-formula content-type="math/mathml"> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="u prime left-parenthesis t right-parenthesis equals upper A left-parenthesis t comma u left-parenthesis t right-parenthesis right-parenthesis comma u left-parenthesis a right-parenthesis equals z"> <mml:semantics> <mml:mrow> <mml:msup> <mml:mi>u</mml:mi> <mml:mo>′</mml:mo> </mml:msup> <mml:mo stretchy="false">(</mml:mo> <mml:mi>t</mml:mi> <mml:mo stretchy="false">)</mml:mo> <mml:mo>=</mml:mo> <mml:mi>A</mml:mi> <mml:mo stretchy="false">(</mml:mo> <mml:mi>t</mml:mi> <mml:mo>,</mml:mo> <mml:mi>u</mml:mi> <mml:mo stretchy="false">(</mml:mo> <mml:mi>t</mml:mi> <mml:mo stretchy="false">)</mml:mo> <mml:mo stretchy="false">)</mml:mo> <mml:mo>,</mml:mo> <mml:mi>u</mml:mi> <mml:mo stretchy="false">(</mml:mo> <mml:mi>a</mml:mi> <mml:mo stretchy="false">)</mml:mo> <mml:mo>=</mml:mo> <mml:mi>z</mml:mi> </mml:mrow> <mml:annotation encoding="application/x-tex">u’(t) = A(t,u(t)),u(a) = z</mml:annotation> </mml:semantics> </mml:math> </inline-formula>, is considered where <inline-formula content-type="math/mathml"> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="upper A colon left-bracket a comma b right-parenthesis times upper D right-arrow upper E"> <mml:semantics> <mml:mrow> <mml:mi>A</mml:mi> <mml:mo>:</mml:mo> <mml:mo stretchy="false">[</mml:mo> <mml:mi>a</mml:mi> <mml:mo>,</mml:mo> <mml:mi>b</mml:mi> <mml:mo stretchy="false">)</mml:mo> <mml:mo>×<!-- × --></mml:mo> <mml:mi>D</mml:mi> <mml:mo stretchy="false">→<!-- → --></mml:mo> <mml:mi>E</mml:mi> </mml:mrow> <mml:annotation encoding="application/x-tex">A:[a,b) \times D \to E</mml:annotation> </mml:semantics> </mml:math> </inline-formula> is continuous, <italic>D</italic> is a closed subset of a Banach space <italic>E</italic>, and <inline-formula content-type="math/mathml"> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="z element-of upper D"> <mml:semantics> <mml:mrow> <mml:mi>z</mml:mi> <mml:mo>∈<!-- ∈ --></mml:mo> <mml:mi>D</mml:mi> </mml:mrow> <mml:annotation encoding="application/x-tex">z \in D</mml:annotation> </mml:semantics> </mml:math> </inline-formula>. With a dissipative type condition on <italic>A</italic>, we establish sufficient conditions for this initial value problem to have a solution. Using these results, we are able to characterize all continuous functions which are generators of nonlinear semigroups on <italic>D</italic>.
We study the existence of periodic solutions of second order nonlinear differential equations by combining the method of upper and lower solutions and the method of Alternative problems. The emphasis … We study the existence of periodic solutions of second order nonlinear differential equations by combining the method of upper and lower solutions and the method of Alternative problems. The emphasis in this paper is on the role of the boundary conditions in the definition of upper and lower solutions.
In recent years the fractional calculus approach to describing dynamic processes in disordered or complex systems such as relaxation or dielectric behavior in polymers or photo bleaching recovery in biologic … In recent years the fractional calculus approach to describing dynamic processes in disordered or complex systems such as relaxation or dielectric behavior in polymers or photo bleaching recovery in biologic membranes has proved to be an extraordinarily successful tool. In this paper we apply fractional relaxation to filled polymer networks and investigate the dependence of the decisive occurring parameters on the filler content. As a result, the dynamics of such complex systems may be well–described by our fractional model whereby the parameters agree with known phenomenological models.
Synopsis A monotone iteration scheme for the solution of the initial boundary problems associated with a system of semilinear parabolic differential equations has been developed that does not require the … Synopsis A monotone iteration scheme for the solution of the initial boundary problems associated with a system of semilinear parabolic differential equations has been developed that does not require the nonlinearities to be quasimonotone. The class of equations to which this scheme applies includes physical models that describe combustion processes involving Arrhenius reaction terms.
Among the iterative schemes for computing the Moore — Penrose inverse of a woll-conditioned matrix, only those which have an order of convergence three or two are computationally efficient. A … Among the iterative schemes for computing the Moore — Penrose inverse of a woll-conditioned matrix, only those which have an order of convergence three or two are computationally efficient. A Fortran programme for these schemes is provided.