Search results for "RECONSTRUCTION"
showing 10 items of 784 documents
Palaeogeographical evolution of the Egadi Islands (western Sicily, Italy). Implications for late Pleistocene and early Holocene sea crossings by huma…
2019
Abstract The continental shelf morphology offshore of western Sicily suggests that during the Last Glacial Maximum (LGM, 20 ka cal BP), two of the Egadi Islands, Favignana and Levanzo, were connected to Sicily by a wide emerged plain, while Marettimo was only separated from the other islands by a narrow channel. We studied the relative sea-level variation from the LGM until today, focussing on two important time slices: the Mesolithic (9.5–13 ka cal BP) and the Neolithic (6.5–7.5 ka cal BP). In this research, we discuss a sea-level rise model by means of geomorphological, archaeological and geophysical observations and new radiocarbon dating of marine and terrestrial fossil fauna. The resul…
Active Lighting Applied to Shape from Polarization
2006
We present a new way of solving the ambiguity that appears in the shape from polarization method. This ambiguity, concerning the normals orientation of the surface, was previously solved thanks to a propagation algorithm. In this paper, the ambiguity is solved thanks to a special active lighting. This method is less time computing and is more robust to noise acquisition. We first demonstrate how to compute the right normals on the whole surface. Then, we show an application on the 3D reconstruction of a specular metallic object made by stamping and polishing.
Hybrid DFT calculations of the atomic and electronic structure for ABO3 perovskite (001) surfaces
2005
Abstract We present the results of first-principles calculations on two possible terminations of the (0 0 1) surfaces of SrTiO3, BaTiO3, and PbTiO3 perovskite crystals. Atomic structure and the electronic configurations were calculated for different 2D slabs, both stoichiometric and non-stoichiometric, using hybrid (B3PW) exchange-correlation technique and re-optimized basis sets of atomic (Gaussian) orbitals. Results are compared with previous calculations and available experimental data. The electronic density distribution near the surface and covalency effects are discussed in details for all three perovskites. Both SrTiO3 and BaTiO3 (0 0 1) surfaces demonstrate reduction of the optical …
Polarization stereoscopic imaging prototype
2011
The polarization of light was introduced last ten years ago in the field of imaging system is a physical phenomenon that can be controlled for the purposes of the vision system. As that found in the human eyes, in general the imaging sensors are not under construction which is sensitive to the polarization of light. These properties can be measured by adding optical components on a conventional camera. The purpose of this thesis is to develop an imaging system that is sensitive both to the stereoscopic and to the state of polarization. As well as the visual system on a various of insects in nature such as bees, that are have capability to move in space by extracted relevant information from…
A Review of Recent Advances in Ear Recognition
2011
Ear recognition has become a rapidly growing research area in recent years. This paper gives an up-to-date review of research works in ear recognition based on 3D data and 2D ear images. For ear recognition in 3D, recent works on 3D feature extraction and model matching are presented and discussed. For 3D ear recognition based on 2D images, 3D ear model reconstruction is mainly discussed. For ear recognition in 2D, main research works on ear detection, ear feature extraction and classification are presented and discussed. Some possible future research interests are proposed in the end.
Avoiding tunnel collisions between fibular collateral ligament and ACL posterolateral bundle reconstruction
2010
PURPOSE: The purpose of this study was to evaluate the risk of tunnel collisions of the fibular collateral ligament (FCL) and posterolateral bundle anterior cruciate ligament (PLB-ACL) tunnels during a combined FCL and double-dundle (DB) ACL reconstruction. METHODS: Thirty-six 4th-generation synthetic femurs (Sawbones, Pacific Research Laboratories, Vashon, WA) were utilized, and two different femur sizes were used. A FCL tunnel and a PLB-ACL tunnel were reamed on each femur. The tunnels of synthetic specimens that did not have a collision were filled with an epoxy resin augmented with BaSO(4) and radiographic evaluation, and Multidetector CT exams of the specimens were performed. RESULTS: …
How to avoid collision between PCL and MCL femoral tunnels during a simultaneous reconstruction.
2014
PURPOSE: The purpose of the present study was to assess the risk of femoral tunnel collisions between the medial collateral ligament (MCL) and the posterior cruciate ligament (PCL) tunnels during a simultaneous PCL and MCL reconstruction. METHODS: Fourth generation medium and large synthetic femur bones were used. On each femur, a MCL tunnel and a PCL tunnel were reamed. The MCL tunnel was drilled at 0°, 20° and 40° of axial and coronal angulations. The PCL femoral tunnel was reamed to simulate two different tunnel directions that could be obtained through an inside-out and outside-in technique. Tunnels were filled with epoxy resin augmented with BaSO4, and a multidetector CT examination of…
Calculation of bone graft volume using 3D reconstruction system.
2010
Objectives: To obtain bone ?bioreplicas? for determining precisely the amount of biomaterial required for bone regeneration procedure. Study design: A case-control comparison with a total sample size of 20 cases, 10 control and 10 test samples. ?Bioreplicas? were generated from helical CAT scans with 0.5 mm slices, without 3D reconstruction or image filters. Bone defects in premolar and molar areas were treated with titanium mesh and xenograft (MP3) combined with resorbable carriers. Time taken to carry out procedures with and without the use of ?bioreplicas? (in minutes), discrepancies between the grafts performed with and without ?bioreplicas? and bone defects (mm), and postoperative comp…
Motion Analysis for Dynamic 3D Scene Reconstruction and Understanding
2017
This thesis studies the problem of dynamic scene 3D reconstruction and understanding using a calibrated 2D-3D camera setup mounted on a mobile platform via the analysis of objects' motions. For static scenes, the sought 3D map reconstruction can be obtained by registering the point cloud sequence. However, with dynamic scenes, we require a prior step of moving object elimination, which yields to the motion detection and segmentation problems. We provide solutions for the two practical scenarios, namely the known and unknown camera motion cases, respectively. When camera motion is unknown, our 3D-SSC and 3D-SMR algorithms segment the moving objects by analysing their 3D feature trajectories.…
The Acts project: track reconstruction software for HL-LHC and beyond
2019
The reconstruction of trajectories of the charged particles in the tracking detectors of high energy physics experiments is one of the most difficult and complex tasks of event reconstruction at particle colliders. As pattern recognition algorithms exhibit combinatorial scaling to high track multiplicities, they become the largest contributor to the CPU consumption within event reconstruction, particularly at current and future hadron colliders such as the LHC, HL-LHC and FCC-hh. Current algorithms provide an extremely high standard of physics and computing performance and have been tested on billions of simulated and recorded data events. However, most algorithms were first written 20 year…