Optimal Parameter Decision Method in VMAT for Lung Tumors with Respiratory Motions

4D VMAT, gated VMAT, and 3D VMAT for stereotactic body radiation therapy in lung.

Four-dimensional volumetric modulated arc therapy (4D VMAT) is a treatment strategy for lung cancers that aims to exploit relative target and tissue motion to improve organ at risk (OAR) sparing. The algorithm incorporates the entire patient respiratory cycle using 4D CT data into the optimization process. Resulting treatment plans synchronize the delivery of each beam aperture to a specific ph...

An optimal analytical method for nonlinear boundary value problems based on method of variation of parameter

In this paper, the authors present a modified convergent analytic algorithm for the solution of nonlinear boundary value problems by means of a variable parameter method and briefly, the method is called optimal variable parameter method. This method, based on the embedding of a parameter and an auxiliary operator, provides a computational advantage for the convergence of the approximate soluti...

Optimal relaxation parameter for the Uzawa Method

We consider the Uzawa method to solve the stationary Stokes equations discretized with stable finite elements. An iteration step consists of a velocity update un+1 involving the (augmented Lagrangian) operator −ν − ρ∇div with ρ ≥ 0, followed by the pressure update pn+1 = p − ανdiv un+1, the so-called Richardson update. We prove that the inf-sup constant β satisfies β ≤ 1 and that, if σ = 1 + ρν...

Determination of Optimal ValveTiming for Internal Combustion Engines Using Parameter Estimation Method

Data mining for decision making in engineering optimal design

Often in modeling the engineering optimization design problems, the value of objective function(s) is not clearly defined in terms of design variables. Instead it is obtained by some numerical analysis such as FE structural analysis, fluid mechanic analysis, and thermodynamic analysis, etc. Yet, the numerical analyses are considerably time consuming to obtain the final value of objective functi...