In this paper, we price American options using the radial basis function (RBF) interpolation method. Two processes for the volatility are assumed: local volatility and stochastic volatility. In particular, we focus on the constant elasticity of variance (CEV) model (Cox and Ross (1976)) and the Heston model (Heston (1993)). Several experiments are performed to evaluate the pricing accuracy and ...

Speaker independent vowel recognition is a di cult pattern recognition problem. Recently therehas been much research using Multi-Layer Perceptrons (MLP) and Decision Trees for this task. Thispaper presents a new approach to this problem. A new neural architecture and learning algorithmcalled Neural Tree Networks (NTN) are developed. This network uses a tree structure with a neural<l...

This paper deals with the identification of nonlinear systems using multi-kernel approach. In this context, we have improved the Support Vector Regression (SVR) method in order to identify nonlinear complex system. Our idea consists in dividing the regressor vector in several blocks, and, for each one a kernel function is used. This blockwise SVR approach is called Support Kernel Regression (SK...

Function approximation has been found in many applications. The radial basis function (RBF) network is one approach which has shown a great promise in this sort of problems because of its faster learning capacity. A traditional RBF network takes Gaussian functions as its basis functions and adopts the least-squares criterion as the objective function, However, it still suffers from two major pr...

The identification of non-linear systems by artificial neural networks has been successfully applied in many applications. In this context, the radial basis function neural network (RBF-NN) is a powerful approach for non-linear system identification. An RBF neural network has an input layer, a hidden layer and an output layer. The neurons in the hidden layer contain Gaussian transfer functions ...

A new learning algorithm called extreme learning machine (ELM) has recently been proposed for single-hidden layer feedforward neural networks (SLFNs) with additive neurons to easily achieve good generalization performance at extremely fast learning speed. ELM randomly chooses the input weights and analytically determines the output weights of SLFNs. It is proved in theory that ELM can be extend...

PURPOSE The purpose of this study was to investigate the response of the retinal arteriole to an acute increase in systemic blood pressure (BP). METHODS Sixteen healthy volunteers underwent a 5-minute cold pressor test (CPT) on the left hand. Retinal blood flow (RBF) was determined using a laser Doppler velocimetry system that enables simultaneous measurements of blood velocity and vessel dia...

BACKGROUND Propranolol and isosorbide-5-mononitrate (ISMN) are increasingly used in the prophylaxis of variceal haemorrhage in cirrhosis. However, recent studies have suggested that these drugs may compromise renal function, possibly by reducing renal blood flow. AIMS To assess the acute effects of propranolol and ISMN on renal blood flow and other haemodynamic parameters in cirrhosis. PATI...

If a hypertensive patient with renal artery stenosis (RAS) is to benefit from percutaneous transluminal renal angioplasty (PTRA) in terms of a sustained improvement in blood pressure control, one may postulate a demonstrable reduction in renal blood flow (RBF) to that kidney, reversible by PTRA. In a population of 32 hypertensive patients, RAS was present in 23 of 62 kidneys. Eleven of the 32 p...

Cardiac output (CO) and renal blood flow (RBF) were simultaneously evaluated by the microsphere method in water-drinking and chronic saline-drinking rats at 3, 12 and 24 hours after induction of acute renal failure by glycerol injection. Threee hours after glycerol injection CO and RBF decreased to 36% and 20% of the respective controls in water-drinking rats and to 41% and 24% of the controls ...