Accurate 3D reconstruction of the surgical scene is important in intra-operative guidance. Existing methods are often based on the assumption that the camera is static or the tissue is deforming with periodic motion. In minimally invasive surgery, these assumptions do not always hold due to free-form tissue deformation induced by instrumenttissue interaction and camera motion required for conti...

Standard direct image registration consists in estimating the geometric warp between a source and a target images by maximizing the photometric similarity for the pixels of a Region of Interest (ROI). The ROI must be included in the real overlap between the images otherwise standard registration algorithms fail. Determining a proper ROI is a hard ‘chicken-and-egg’ problem since the overlap is o...

Gamma oscillations are thought to be critical for a number of behavioral functions, they occur in many regions of the brain and through a variety of mechanisms. Fast repetitive bursting (FRB) neurons in layer 2 of the cortex are able to drive gamma oscillations over long periods of time. Even though the oscillation is driven by FRB neurons, strong feedback within the rest of the cortex must mod...

This paper presents a free-form deformation technique suitable for aerodynamic shape optimization. Because the proposed technique is independent of grid topology, we can treat structured and unstructured computational fluid dynamics grids in the same manner. The proposed technique is an alternative shape parameterization technique to trivariate volume technique. It retains the flexibility and f...

It is crucial for the users to touch, grasp and manipulate the interested objects through our sense of touch in many interactive applications, such as on-line computer games, interactive cartoon design, and virtual prototyping. In this paper, we propose an interactive haptic deformation approach which incorporates the dynamic simulation of mass–spring systems and flexible control of free-form d...

The Free-Form Deformation (FFD) methods are a family of intuitive, efficient and versatile free-form modelling techniques, which rely on an ambient warp of the space cocooning an embedded object. However, the distortion caused by FFD significantly degrades the approximation quality of polygon-mesh objects. We present a curvature-based adaptive refinement and decimation algorithm which solves th...

One challenge that remains open in 3D deep learning is how to efficiently represent 3D data to feed deep networks. Recent works have relied on volumetric or point cloud representations, but such approaches suffer from a number of issues such as computational complexity, unordered data, and lack of finer geometry. This paper demonstrates that a mesh representation (i.e. vertices and faces to for...

A nonabelian class of massless/massive nonlinear gauge theories of YangMills vector potentials coupled to Freedman-Townsend antisymmetric tensor potentials is constructed in four spacetime dimensions. These theories involve an extended Freedman-Townsend type coupling between the vector and tensor fields, and a Chern-Simons mass term with the addition of a Higgs type coupling of the tensor field...