in this paper, at rst for a given set of real or complex numbers  with nonnegative summation, we introduce some special conditions that with them there is no nonnegative tridiagonal matrix in which  is its spectrum. in continue we present some conditions for existence such nonnegative tridiagonal matrices.

‎in this paper‎, ‎we find matrix representation of a class of sixth order sturm-liouville problem (slp) with separated‎, ‎self-adjoint boundary conditions and we show that such slp have finite spectrum‎. ‎also for a given matrix eigenvalue problem $hx=lambda vx$‎, ‎where $h$ is a block tridiagonal matrix and $v$ is a block diagonal matrix‎, ‎we find a sixth order boundary value problem of atkin...

‎In this paper‎, ‎we find matrix representation of a class of sixth order Sturm-Liouville problem (SLP) with separated‎, ‎self-adjoint boundary conditions and we show that such SLP have finite spectrum‎. ‎Also for a given matrix eigenvalue problem $HX=lambda VX$‎, ‎where $H$ is a block tridiagonal matrix and $V$ is a block diagonal matrix‎, ‎we find a sixth order boundary value problem of Atkin...

we investigate the boundary-value problem generated by the sturm-liouville equation withdiscontinuous coefficients, eigenparameter dependent boundary conditions and transmission conditionsat the point of discontinuity. with a different approach we introduce an adequate hilbert spaceformulation, investigate some properties of eigenvalues, green’s function and resolvent operator, andfind simple c...

In this paper, it is shown that by exploiting the explicit parametric state feedback solution, it is feasible to obtain the ultimate solution to minimum sensitivity problem. A numerical algorithm for construction of a robust state feedback in eigenvalue assignment problem for a controllable linear system is presented. By using a generalized parametric vector companion form, the problem of eigen...

This paper introduces the notion of a transcendental problem motivated by the needs to engineer the system which can evolve as the situation changes. The problem is generally called transcendental if it addresses the solution adequacy of the system that is implemented without any provision for subsequent requirement changes. Subsequently, the transcendental problem evident in Turing’s test is a...

We consider the heat equation with spatially variable thermal conductivity and homogeneous Dirichlet boundary conditions. Using Method of Fokas or Unified Transform Method, we derive solution representations as limit solutions constant-coefficient interface problems where number subdomains interfaces becomes unbounded. This produces an explicit representation solution, from which can compute de...