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A new approach for solving nonlinear BVP's on the half-line for second order equations and applications

Serena Matucci (2015)

Mathematica Bohemica

We present a new approach to solving boundary value problems on noncompact intervals for second order differential equations in case of nonlocal conditions. Then we apply it to some problems in which an initial condition, an asymptotic condition and a global condition is present. The abstract method is based on the solvability of two auxiliary boundary value problems on compact and on noncompact intervals, and uses some continuity arguments and analysis in the phase space. As shown in the applications,...

A new characteristic property of Mittag-Leffler functions and fractional cosine functions

Zhan-Dong Mei, Ji-Gen Peng, Jun-Xiong Jia (2014)

Studia Mathematica

A new characteristic property of the Mittag-Leffler function E α ( a t α ) with 1 < α < 2 is deduced. Motivated by this property, a new notion, named α-order cosine function, is developed. It is proved that an α-order cosine function is associated with a solution operator of an α-order abstract Cauchy problem. Consequently, an α-order abstract Cauchy problem is well-posed if and only if its coefficient operator generates a unique α-order cosine function.

A new continuous dependence result for impulsive retarded functional differential equations

Márcia Federson, Jaqueline Godoy Mesquita (2016)

Czechoslovak Mathematical Journal

We consider a large class of impulsive retarded functional differential equations (IRFDEs) and prove a result concerning uniqueness of solutions of impulsive FDEs. Also, we present a new result on continuous dependence of solutions on parameters for this class of equations. More precisely, we consider a sequence of initial value problems for impulsive RFDEs in the above setting, with convergent right-hand sides, convergent impulse operators and uniformly convergent initial data. We assume that the...

A new look at an old comparison theorem

Jaroslav Jaroš (2021)

Archivum Mathematicum

We present an integral comparison theorem which guarantees the global existence of a solution of the generalized Riccati equation on the given interval [ a , b ) when it is known that certain majorant Riccati equation has a global solution on [ a , b ) .

A new method of proof of Filippov’s theorem based on the viability theorem

Sławomir Plaskacz, Magdalena Wiśniewska (2012)

Open Mathematics

Filippov’s theorem implies that, given an absolutely continuous function y: [t 0; T] → ℝd and a set-valued map F(t, x) measurable in t and l(t)-Lipschitz in x, for any initial condition x 0, there exists a solution x(·) to the differential inclusion x′(t) ∈ F(t, x(t)) starting from x 0 at the time t 0 and satisfying the estimation x ( t ) - y ( t ) r ( t ) = x 0 - y ( t 0 ) e t 0 t l ( s ) d s + t 0 t γ ( s ) e s t l ( τ ) d τ d s , where the function γ(·) is the estimation of dist(y′(t), F(t, y(t))) ≤ γ(t). Setting P(t) = x ∈ ℝn: |x −y(t)| ≤ r(t), we may formulate the conclusion in Filippov’s theorem...

A new model to describe the response of a class of seemingly viscoplastic materials

Sai Manikiran Garimella, Mohan Anand, Kumbakonam R. Rajagopal (2022)

Applications of Mathematics

A new model is proposed to mimic the response of a class of seemingly viscoplastic materials. Using the proposed model, the steady, fully developed flow of the fluid is studied in a cylindrical pipe. The semi-inverse approach is applied to obtain an analytical solution for the velocity profile. The model is used to fit the shear-stress data of several supposedly viscoplastic materials reported in the literature. A numerical procedure is developed to solve the governing ODE and the procedure is validated...

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