Numerical evaluation of cauchy principal values of integrals

Gaussian quadrature rules for the evaluation of Cauchy principal values of integrals are considered, their relation with Gauss-Legendre formulas is studied, and they are compared with other rules.     

A characterization of distributions of independent random vectors by the independence of transformed vectors

If W and Z are independent random vectors and Y₁, Y₂, …, Y_n are the result of a transformation satisfying certain general conditions then W and Z are distributed according to a certain class of densities if and only if for suitable q, (Y₁, …, Y_q) and (Y_q+1, …, Y_n) are independent.     

On the application of substochastic semigroup theory to fragmentation models with mass loss

A linear integro-differential equation modelling multiple fragmentation with inherent mass loss is investigated by means of substochastic semigroup theory. The existence of a semigroup is established and, under natural conditions on certain coefficients, the generator of this semigroup is identified. This yields, in particular, a validation of the formal mass-loss rate equation for the model.     

A mean-value theorem and its applications

For a function f defined in an interval I, satisfying the conditions ensuring the existence and uniqueness of the Lagrange mean L[f], we prove that there exists a unique two variable mean M[f] such that

     

Global well-posedness for Keller-Segel system in Besov type spaces

The Cauchy problems for Keller-Segel system are studied using homogeneous Besov spaces. With the homogeneous Besov spaces , which is the scaling critical case for Keller-Segel system, global solutions for small initial data are obtained in the space. In addition, ill-posedness for Keller-Segel system is also studied.     

Integration over non-rectifiable curves and Riemann boundary value problems

In this paper we introduce an alternative way of defining the curvilinear Cauchy integral over non-rectifiable curves in the case of complex functions of one complex variable. Especially the jump behavior on the boundary is considered. As an application, solvability conditions of the Riemann boundary value problem are derived on very weak conditions to the boundary. Besides the complex case the consideration can be extended to the theory of Douglis algebra valued functions.     

Approximate controllability of second‐order distributed systems

In this paper, we study the approximate controllability of control systems with state and control in Banach spaces and described by a second‐order semilinear abstract differential equation. We compare the approximate controllability of the system with the approximate controllability of an associated discrete system. Copyright © 2013 John Wiley & Sons, Ltd.     

ON THE METHOD OF SOLUTION FOR A KIND OFNONLINEAR SINGULAR INTEGRAL EQUATION

The solutions of the nonlinear singular integral equation ψo(t)2 2b/πi ∫L ψ(τ)/T-t dr =f(t), t ∈ L, are considered, where L is a closed contour in the complex plane, b ≠- 0 is a constant and f(t) is a polynomial. It is an extension of the results obtained in [1] when f(t) is a constant. Certain special cases are illustrated.     

Ornstein–Uhlenbeck process,Cauchy process,and Ornstein–Uhlenbeck–Cauchy process on a circle

By a simple mathematical method, we obtain the transition probability density functions of the Ornstein–Uhlenbeck process, Cauchy process, and Ornstein–Uhlenbeck–Cauchy process on a circle.