The design of physiological motion compensation systems for robotic-assisted cardiac Minimally Invasive Surgery (MIS) is a challenging research topic. In this domain, vision-based techniques have proven to be a practical way to retrieve the motion of the beating heart. However due to the complexity of the heart motion and its surface characteristics, efficient tracking is still a complicated ta...

This thesis describes the methods used to analyse and model the cutting of pig carcasses into the products: back, belly, spine and ribs. Automatic pre-processing methods to segment out the individual products from raw DICOM images are developed. A bit resolution reduction method is presented for producing images that are readable for other software. Image registration method are studied and use...

In this paper we address the problem of registering 3D scattered data by the mean of a statistical shape model. This model is built from a training set on which a principal component analysis ( E A ) is applied. A local system of reference is computed for each sample shape of the learning set, what enables to align the training set. PCA then reveals the main modes of deformation of the class of...

Abstract. Radial basis function (RBF) interpolation can be very effective for scattered data in any number of dimensions. As one of their many applications, RBFs can provide highly accurate collocation-type numerical solutions to several classes of PDEs. To better understand the accuracy that can be obtained, we survey here derivative approximations based on RBFs using a similar Fourier analysi...

In this technical report, we propose a novel technique to address motion estimation and tracking. Such technique represents the motion field using a regular grid of thin-plate splines, and the moving objects using an implicit function on the image plane that is a cubic interpolation of a ”level set function” defined on this grid. Optical flow is determined through the deformation of the grid an...

In recent years, research efforts to extend linear metric learning models to handle nonlinear structures have attracted great interests. In this paper, we propose a novel nonlinear solution through the utilization of deformable geometric models to learn spatially varying metrics, and apply the strategy to boost the performance of both kNN and SVM classifiers. Thin-plate splines (TPS) are chosen...

A subdomain variational inequality and its meshless linear complementary formulation are developed in the present paper for solving two-dimensional contact problems. The subdomain variational inequality will be defined in detail. The meshless method is based on a local weighted residual method with the Heaviside step function as the weighting function over a local subdomain and radial basis fun...

The choice of an appropriate interpolation technique is an imposing task. There are many techniques to choose from depending on the characteristics of the phenomenon, the purpose of the study and also the expertise of the user. This paper describes the implementation and architecture of a Java-based intelligent advisor to assist a generic user, ranging from the casual to the specialist, in sele...

Fingerprint mosaicing entails the reconciliation of information presented by two or more impressions of a finger in order to generate composite information. It can be accomplished by blending these impressions into a single mosaic, or by integrating the feature sets (viz., minutiae information) pertaining to these impressions. In this work, we use Thin-plate Splines (TPS) to model the relative ...