The decomposition of nonlinear problems

We show that under certain conditions nonlinear programming problems can be decomposed into a series of smaller problems.A Decomposition Theorem and example are presented.     

Nonlinear analysis and complementarity theory

We present in this paper a short survey of some recent interactions between Nonlinear Analysis and Nonlinear Complementarity. Considering the new relations between Nonlinear Analysis and Complementarity Theory, put in evidence in this paper, we define several open research subjects profitable to both domains.     

A numerical solution of nonlinear Volterra-Fredholm integral equations

In this paper, a numerical procedure for solving a class ofnonlinear Volterra-Fredholm integral equations is presented. Themethod is based upon the globally defined sinc basis functions.Properties of the sinc procedure are utilized to reduce thecomputation of the nonlinear integral equations to some algebraicequations. Illustrative examples are included to demonstrate thevalidity and applicability of the method.     

HIGH-ORDER NONLINEAR GALERKIN METHODS

The nonlinear Galerkin methods are numerical schemes well adapted to the long-term integration of nonlinear evolution partial differential equations. In this paper, a class of high-order nonlinear Galerkin methods are provided. Moreover, convergence results with high-order spectral accuracy are derived for the schemes introduced.     

A global quadratic algorithm for solving a system of mixed equalities and inequalities

A new algorithm is proposed which, under mild assumptions, generates a sequence{x _i } that starting at any point inR ⁿ will converge to a setX defined by a mixed system of equations and inequalities. Any iteration of the algorithm requires the solution of a linear programming problem with relatively few constraints. By only assuming that the functions involved are continuously differentiable a superlinear rate of convergence is achieved. No convexity whatsoever is required by the algorithm.     

State estimation in batch processes using a nonlinear observer

This paper deals with the problem of nonlinear states estimation in batch chemical processes. It presents a reduced-order nonlinear observer approach to perform the estimation. The proposed method allows adjustment of the speed of convergence towards zero of the estimation error. The stability properties of the model-based observer are analytically treated in order to show the conditions under which exponential convergence can be achieved. In addition, the performance of the proposed observer is evaluated on batch processes.     

REITERATED HOMOGENIZATION OF NONLINEAR MONOTONE OPERATORS

61. IntroductionLet us consider the clajss of partial differential equations of the form--div(a.(x, Du.)) ~ f on fi, us E Wt,p(fl), (1.1)where a6 is increasingly oscillating as E -- 0, fi is an open bounded subset of R", 1 < p < cot1/p 1/q = 1 and f E W--"q(fl). The homogenization problem for (l.1) consists of the studyof the asymptotic behavior of solutions net as e - 0. In many important cases nE convergesweakly in WI'p(n) to the solution no of the homogenized problem--div(b(Duo)) = f …     

Global attractor for a class of nonlinear lattices

We consider a class of nonlinear lattices with nonlinear damping

(0.1)     

Optimal budget allocation when response is S-shaped

We consider the profit maximizing allocation of a budget among n activities when the revenue from each activity is an S-shaped function of the budget allocated to it. Results are obtained for functions that cross only in the convex part. A simple computational procedure based on these results is presented. The results are specialized to cases where the functions do not cross, are multiples of the same function, are identical, and are piecewise linear.     

Nonlinear feedback controllers and compensators: a state-dependent Riccati equation approach

State-dependent Riccati equation (SDRE) techniques are rapidly emerging as general design and synthesis methods of nonlinear feedback controllers and estimators for a broad class of nonlinear regulator problems. In essence, the SDRE approach involves mimicking standard linear quadratic regulator (LQR) formulation for linear systems. In particular, the technique consists of using direct parameterization to bring the nonlinear system to a linear structure having state-dependent coefficient matrices. Theoretical advances have been made regarding the nonlinear regulator problem and the asymptotic stability properties of the system with full state feedback. However, there have not been any attempts at the theory regarding the asymptotic convergence of the estimator and the compensated system. This paper addresses these two issues as well as discussing numerical methods for approximating the solution to the SDRE. The Taylor series numerical methods works only for a certain class of systems, namely with constant control coefficient matrices, and only in small regions. The interpolation numerical method can be applied globally to a much larger class of systems. Examples will be provided to illustrate the effectiveness and potential of the SDRE technique for the design of nonlinear compensator-based feedback controllers.     

Structure of the first-order solution set for a class of nonlinear programs with parameters

This paper studies the set of first-order solutions of a family of nonlinear programs in which the inequality constraints are fixed but the right hand side of the equality constraints varies. It is shown that under certain conditions this set is a topological manifold. The results are applied to the problem of describing the set of first-order Pareto optima in a pure exchange economy with monotone utility functions.     

On the functional variable method for finding exact solutions to a class of wave equations

We present an alternative functional variable method or briefly called FVM (in short) to analyze a class of wave equations, consisting in construction of exact travelling solutions. Some important nonlinear model equations which arise in a wide variety of physical problems have been presented as testbed to show the application of this method.     

The newton method for C1αmaps In anach Spaceis$fr1;∗$f:∗

On the basis of a work by B.Döring for ?¹→ ?¹maps we give a thourough proof of the convergence and on the convergence speed of the Newton Method for C ¹αmaps in Banach spaces. We describe the application of this classical method for the existence (and local uniqueness and approximation) of nonlinear eigenvalue problems - abstractly - and for the concrete case of nonlinear Dirichlet problem which was for- merly attacked by variational methods     

The continuous collapsing Knapsack problem

A Collapsing Knapsack is a container whose capacity diminishes as the number of items it must hold is increased. This paper focuses on those cases in which the decision variables are continuous, i.e., can take any non-negative value. It is demonstrated that the problem can be reduced to a set of two dimensional subproblems. Strategies for elimination of subproblems and conditions permitting reduction to a set of one dimensional problems are also considered. Computational results indicate that the procedure is quite efficient. Even for large problems only a small number of subproblems have to be solved.     

A constrained optimization approach to solving certain systems of convex equations

This research presents a new constrained optimization approach for solving systems of nonlinear equations. Particular advantages are realized when all of the equations are convex. For example, a global algorithm for finding the zero of a convex real-valued function of one variable is developed. If the algorithm terminates finitely, then either the algorithm has computed a zero or determined that none exists; if an infinite sequence is generated, either that sequence converges to a zero or again no zero exists. For solving n-dimensional convex equations, the constrained optimization algorithm has the capability of determining that the system of equations has no solution. Global convergence of the algorithm is established under weaker conditions than previously known and, in this case, the algorithm reduces to Newton’s method together with a constrained line search at each iteration. It is also shown how this approach has led to a new algorithm for solving the linear complementarity problem.     

NONLINEAR EXPECTATIONS AND NONLINEAR MARKOV CHAINS

§1.IntroductionLet(?,F)be a measurable space and let Lb(F)be the space of F-measurable andbounded real functions.A nonlinear expectation is a continuous functionalE[·]:Lb(F)?→Rthat is order preserving(i.e.,E[X1]≥E[X2],if X1≥X2)and constant preserving     

A cubic differential system with nine limit cycles

Advances in Computer Algebra software have made calculations possible that were previously intractable. Our particular interest is in the investigation of limit cycles of nonlinear differential equations. We describe some recent developments in handling very large computations involving resultants and present an example of a nonlinear differential system of degree three with nine small amplitude limit cycles surrounding a focus. We know of no examples of cubic systems with more than this number bifurcating from a fine focus, as opposed to a centre. Our example appears to be the first to have been obtained without recourse to some numerical calculation.     

Nonlinear control of systems with multiple equilibria and unknown sinusoidal disturbance

In this paper, nonlinear systems having multiple equilibrium points and low order dynamics are investigated. Roll motions of ships are studied by means of modern nonlinear techniques to exemplify the behavior of such nonlinear systems in the case when they are under the influence of external sinusoidal disturbances with unknown amplitudes. The main objective is to analyze the performance of this system at different operating conditions, including those giving rise to chaos, and to design a controller with an overparameterized structure to stabilize the system at the origin. A nonlinear recursive backstepping controller is proposed and the transient performance is investigated. Lyapunov-based techniques are used to force systematic following of a reference model while introducing a nonlinear parameter estimator to guarantee adaptivity. Robustness problems as well as ways to tune the controller parameters are examined. Simulation results are submitted for the uncontrolled and controlled cases, verifying the effectiveness of the proposed controller. Finally, a discussion and conclusions are given with possible future extensions.