in this paper, we present a fractional mathematical model of a one-dimensional phase phase change problem (stefan problem) with latent heat a power function of position. this model includes space-time fractional derivatives in caputo sense and time dependent surface heat flux. an approximate solution of this model is obtained by optimal homotopy asymptotic method (oham) to find an approximate s...

This paper is concerned with the optimal distributed control problem governed by b-equation. We firstly investigate the existence and uniqueness of weak solution for the controlled system with appropriate initial value and boundary condition. By contrasting with our previous result, the proof without considering viscous coefficient is a big improvement. Secondly, based on the well-posedness res...

In this paper, the optimal conditions for fractional optimal control problems (FOCPs) were derived in which the fractional differential operators defined in terms of Caputo sense and reduces this problem to a system of fractional differential equations (FDEs) that is called twopoint boundary value (TPBV) problem. An approximate solution of this problem is constructed by using the Legendre-Gauss...

abstract the use of water sources has increased due to extend of agricultural activity for answering food needs of increasing population. while because of exploitation and consumption of water, the use of this restricted resource is not appropriate. consequently in many districts of country the head level of ground water aquifers have been fallen and water level is negative. so, application of ...

In this paper we study the following problem: Discrete partitioning problem (DPP): Let FqP denote the n-dimensional finite projective space over Fq. For positive integer k ≤ n, let {A}i=1 be a partition of (FqP ) such that 1. for all i ≤ N , A = ∏k j=1 A i j (partition into product sets), 2. for all i ≤ N , there is a (k − 1)-dimensional subspace L ⊆ FqP such that A ⊆ (L). What is the minimum v...

For autonomous, nonlinear, smooth optimal control systems on n-dimensional manifolds we investigate the relationship between the discounted and the average yield optimal value of infinite horizon problems. It is shown that the value functions of discounted problems converge to the value function of the average yield problem as the discount rate tends to zero, if there exist approximately optima...

The use of vector valued performance index as a performance measure in the design of optimal control systems has invited much attention from researchers in the field of control engineering. The problem is of practical significance as the system presents an optimal solution for multiple criteria optimal control problems. A general performance index is defined in the form of a norm which can be e...

In this paper, a minimum and near-minimum time optimal control laws are developed and compared for a rigid space platform with flexible links during an orientating maneuver with large angle of rotation. The control commands are considered as typical bang-bang with multiple symmetrical switches, the time optimal control solution for the rigid-body mode is obtained as a bang-bang function and app...

Optimal design, parameter estimation, and inverse problems arising in the modeling of semiconductor devices lead to optimization problems constrained by systems of PDEs. We study the impact of different state equation discretizations on optimization problems whose objective functionals involve flux terms. Galerkin methods, in which the flux is a derived quantity, are compared with mixed Galerki...