thermal contact conductance (tcc) between an exhaust valve and its seat is one of the important parameters to be estimated in an internal combustion engine. an experimental study presented here to acquire temperature in some interior points to be used as inputs to an inverse analysis. an actual exhaust valve and its seat are utilized in a designed and constructed setup. conjugate gradient metho...

We study an interior-point gradient method for solving a class of so-called totally nonnegative least squares problems. At each iteration, the method decreases the residual norm along a diagonally scaled negative gradient direction with a special scaling. We establish the global convergence of the method, and present some numerical examples to compare the proposed method with a few similar meth...

In this paper we study the initial-boundary value problems for nonlinear parabolic equations without Bernstein-Nagumo condition. Sufficient conditions guaranteeing the nonexistence of gradient blow-up are formulated. In particular, we show that for a wide class of nonlinearities the Lipschitz continuity in the space variable together with the strict monotonicity with respect to the solution gua...

The ultraconvergence property of a gradient recovery technique proposed by Zienkiewicz and Zhu is analyzed for the Laplace equation in the two dimensional setting. Under the assumption that the pollution effect is not present or is properly controlled, it is shown that the convergence rate of the recovered gradient at an interior node is two orders higher than the optimal global convergence rat...

This papers studies the performance of several interior-point and activeset methods on bound constrained optimization problems. The numerical tests show that the sequential linear-quadratic programming (SLQP) method is robust, but is not as effective as gradient projection at identifying the optimal active set. Interiorpoint methods are robust and require a small number of iterations and functi...

We examined the role of pH gradient and membrane potential in dipeptide transport in purified intestinal and renal brush-border membrane vesicles which were predominantly oriented right-side out. With an intravesicular pH of 7.5, changes in extravesicular pH significantly affected the transport of glycyl-L-proline and L-carnosine, and optimal dipeptide transport occurred at an extravesicular pH...

People attending teleconference meetings usually follow specific trajectories corresponding to their intentions. In most situations the meeting video content can by sufficiently characterized by capturing the head trajectories. The tracking of the head is done using a particle filter built on cues such as color, gradient and shape. The head is represented by an ellipse with fuzzy color histogra...

We study the problem of finding a local minimum of a multilinear function E over the discrete set {0, 1}. The search is achieved by a gradient-like system in [0, 1] with cost function E. Under mild restrictions on the metric, the stable attractors of the gradient-like system are shown to produce solutions of the problem, even when they are not in the vicinity of the discrete set {0, 1}. Moreove...