Search results for " Mesh"

Dealing with reconstruction problems: two cases study

Reconstruction problems are always included in a computer vision system as one of the key step toward the recognition of a scene. There are hierarchies of reconstruction that go from pixels to regions in the lower level, and from patches to objects in higher steps. The success of the reconstruction phase de-pends on several factors: the selection of "suitable" features, the matching function, the linking strategy. I this paper we show some of problems and solutions in two different contexts: the 3D reconstruction from cloud of points representing fragments of archeological finding, and the mosaicing from sea bed video frames. Preliminary results show that in both cases the accuracy is satis…

On invariant manifolds of saddle points for 3D multistable models

2017

In dynamical systems a particular solution is completely determined by the parameters considered and the initial conditions. Indeed, when the model shows a multistability, starting from different initial state, the trajectories can evolve towards different attractors. The invariant manifolds of the saddle points separate the vector field into the basins of attraction of different stable equilibria. The aim of this work is the reconstruction of these separation surfaces in order to know in advance the geometry of the basins. In this paper three-dimensional models with three or more stable fixed points is investigated. To this purpose a procedure for the detection of the scattered data lying …

Smoothed Particle Electromagnetics Modelling on HPC-GRID Environment

2012

In this paper a meshless approach on a high performance grid computing environment to run fast onerous electromagnetic numerical simulations, is presented. The grid computing and the message passing interface standard have been employed to improve the computational efficiency of the Smoothed Particle Electromagnetics meshless solver adopted. Applications involving an high number of particles can run on a grid computational environment simulating complex domains not accessible before and offer a promising approach for the coupling of particle models to continuous models. The used meshless solver is straightforward to program and fully parallelizable. The results of the parallel numerical sch…

Laparoscopic lower lateral incisional hernia repair after kidney transplant

2015

Use of tailored intraperitoneal ePTFE dual mesh in permagna inguinal hernia

2012

Here we report a case of a giant inguinoscrotal hernia in an elderly patients treated by means of an open positioning of intraperitoneal ePTFE dual mesh. In patients with giant inguinoscrotal hernia the forceful introduction of viscera in abdominal cavity and primary wall closure is burnened from respiratory complication, abdominal compartment syndrome, and defects in wound healing thus exposing the patients to further morbidity and mortality risk. The management of these patients is difficult because of the high occurrence of morbidity factors that affect the success on intervention independently of the technique of surgical repair. The tension- free technique we adopted consented us to ob…

USE OF INTRAPERITONEAL PTFE DUAL-MESH IN A GIANT INCISIONAL HERNIA AFTER RENAL TRANSPLANTATION: A CASE REPORT

2008

Objectives: We evaluated the incidence of incisional hernia after kidney transplantation, predisposing factors and the results of surgical repair of a giant incisional hernia by intraperitoneal PTFE dual mesh. Patients and methods: We report our experience about an incisional hernia in a 55 years male after renal transplantation treated with an intraperitoneal dual mesh prosthesis. The cause of incisional hernia was probably due to an urinoma for a total necrosis of distal graft ureter that needed to reopen in 2sd day post transplant with primary fascial approximation. Thirty days after transplantation we discovered a large incisional hernia that rapidly became monstrous with migration of o…

HUMAN FIBRIN GLUE SEALING VERSUS SUTURE POLYPROPYLENE FIXATION IN LICHTENSTEIN INGUINAL HERNIORRAPHY: A PROSPECTIVE OBSERVATIONAL STUDY.

2014

Background: Patients who underwent primary inguinal hernia repair still report a high rate of postoperative pain after operation due to effect of mesh fixation by suture. An alternative is the use of human fibrin glue. We compared the two techniques. Methods: 468 patients randomly underwent primary inguinal hernia Lichtenstein repair fixing the mesh by suture or by human fibrin glue (HFG); in both cases themesh was fixed to the posterior wall of the inguinal canal and to the inguinal legament. results: No significant differences were recorded between the two groups in terms of complications, while the sutureless technique reduces the operative time and the postoperative pain. Conclusions: A…

The use of a tailored mesh with special design for ventral hernia repair. Preliminary report

2009

Introduction: The study describes a modified technique for ventral hernia repair based upon a tension free, fixation free, and dynamic compliant implant. Material and methods: A unique geometrical shaped light weighted, large porous polypropylene mesh was created consisting of a large central body and six radial arms, designed to pass through the tissues and hold the mesh in place without tension. We used the mesh in a small exploratory cohort of patients with ventral hernia. The mesh was placed sublay by taking each of the six straps and passing from below the muscle, through the muscle allowing the fixation free strap to sit with friction within the tissues. This was designed to give a te…

MAST solution of irrotational flow problems in 2D domains with strongly unstructured triangular meshes

2010

A new methodology for the solution of irrotational 2D flow problems in domains with strongly unstructured meshes is presented. A fractional time step procedure is applied to the original governing equations, solving consecutively a convective prediction system and a diffusive corrective system. The non linear components of the problem are concentrated in the prediction step, while the correction step leads to the solution of a linear system, of the order of the number of computational cells. A MArching in Space and Time (MAST) approach is applied for the solution of the convective prediction step. The major advantages of the model, as well as its ability to maintain the solution monotonicit…

A comparison of local parametric C0 Bézier interpolants for triangular meshes

2011

Parametric curved shape surface schemes interpolating vertices and normals of a given triangular mesh with arbitrary topology are widely used in computer graphics for gaming and real-time rendering due to their ability to effectively represent any surface of arbitrary genus. In this context, continuous curved shape surface schemes using only the information related to the triangle corresponding to the patch under construction, emerged as attractive solutions responding to the requirements of resource-limited hardware environments. In this paper we provide a unifying comparison of the local parametric C^0 curved shape schemes we are aware of, based on a reformulation of their original constr…