Search results for "RECONSTRUCTION"
showing 10 items of 784 documents
Seasonal changes in sediment core PS1795-2
2014
The Weddell Sea and the associated Filchner-Rønne Ice Shelf constitute key regions for global bottomwater production today. However, little is known about bottom-water production under different climate and icesheet conditions. Therefore, we studied core PS1795, which consists primarily of fine-grained siliciclastic varves that were deposited on contourite ridges in the southeastern Weddell Sea during the Last Glacial Maximum (LGM). We conducted high-resolution X-ray fluorescence (XRF) analysis and grain-size measurements with the RADIUS tool (Seelos and Sirocko, 2005, doi:10.1111/j.1365-3091.2005.00715.x) using thin sections to characterize the two seasonal components of the varves at sub-…
Reconstruction of the internal structure of the pore system of a complex dinosaur eggshell (Megaloolithus siruguei)
2013
Despite the many reconstructions of fossil material that have recently appeared in the literature, dinosaur eggshells have never been reconstructed using computing techniques. Using the EMAC 3-D modelling methodology, we reconstruct a section of the Late Cretaceous Megaloolithus siruguei eggshell, which has a particularly complex pore system, exhibiting an intricate network of vertical, oblique, and horizontal pores.
Combining Mendonça-Cipolla self-calibration and scene constraints
2011
International audience; In this paper, we propose a method that combines plane parallelism and the Mendonça/Cipolla self-calibration constraints. In our method each pair of images is treated independently and can therefore use a different pair of parallel planes not necessarily visible in the other views. While, for each pair of images, constraints on the singular values of the essential matrix provide two algebraic constraints on the intrinsic parameters, those we derive from plane parallelism have the advantage of providing two additional ones making the calibration of a no-skew camera possible from two images only.
Mandibular Brown Tumor as a Result of Secondary Hyperparathyroidism: A Case Report with 5 Years Follow-Up and Review of the Literature
2021
Background: Brown tumor is a rare skeletal manifestation of secondary hyperparathyroidism. Although diagnosis of the disease is increasingly seen in early stages due to improved screening techniques, some patients still present in a progressed disease stage. The treatment depends on tumor mass and varies from a conservative approach with supportive parathyroidectomy to extensive surgical resection with subsequent reconstruction. Case presentation: We report a case of extensive mandibular brown tumor in a patient with a history of systemic lupus erythematosus, chronic kidney disease, and secondary hyperparathyroidism. Following radical resection of the affected bone, reconstruction could be …
Nuclear structure functions at a future electron-ion collider
2017
The quantitative knowledge of heavy nuclei's partonic structure is currently limited to rather large values of momentum fraction $x$---robust experimental constraints below $x\ensuremath{\sim}{10}^{\ensuremath{-}2}$ at low resolution scale ${Q}^{2}$ are particularly scarce. This is in sharp contrast to the free proton's structure which has been probed in Deep Inelastic Scattering (DIS) measurements down to $x\ensuremath{\sim}{10}^{\ensuremath{-}5}$ at perturbative resolution scales. The construction of an electron-ion collider (EIC) with a possibility to operate with a wide variety of nuclei, will allow one to explore the low-$x$ region in much greater detail. In the present paper we simula…
The COMPASS Setup for Physics with Hadron Beams
2015
The main characteristics of the COMPASS experimental setup for physics with hadron beams are described. This setup was designed to perform exclusive measurements of processes with several charged and/or neutral particles in the final state. Making use of a large part of the apparatus that was previously built for spin structure studies with a muon beam, it also features a new target system as well as new or upgraded detectors. The hadron setup is able to operate at the high incident hadron flux available at CERN. It is characterised by large angular and momentum coverages, large and nearly flat acceptances, and good two and three-particle mass resolutions. In 2008 and 2009 it was successful…
La ricostruzione da immagini con tecniche di restituzione prospettica
2018
Il contributo è incentrato sulla ricostruzione di opere di architettura perdute da fotografie attraverso l’uso di tecniche di restituzione prospettica. Una breve introduzione illustra le ragioni che relegano la restituzione prospettica a un ruolo secondario nel contesto delle ricostruzioni virtuali; il paragrafo successivo illustra i risultati di un test sul confronto fra restituzione prospettica da singolo fotogramma e restituzione SfM. Il paragrafo conclusivo descrive la ricostruzione virtuale di una chiesa di Palermo, demolita nella prima metà del XX secolo e documentata da poche foto d’epoca. The paper focuses the 3D reconstruction of buildings that were destroyed during the World War I…
PERSPECTIVE RESTITUTION FROM VIEW CAMERAS PHOTOS
2022
Abstract. The paper aims at discussing the accuracy of perspective restitution from view camera photos; view cameras are non-standard cameras frequently used in the past century for on field shooting of buildings and urban sites; this is why the reconstruction of lost buildings often deals with photos taken with a view camera. The case study chosen for the proposed experiment is an urban complex built in Palermo in the ‘50s. The site features a very regular layout with surfaces at right angle, that supports the graphic reconstruction of photos’ inner and outer orientation. The site has been surveyed with a laser scanner; the point cloud provided the metric information needed for the evaluat…
Dalla Fotografia alla ricostruzione: Porta Maqueda a Palermo
2022
The reconstruction of gone, or never built buildings has ever been one of the preferred subjects of digital representation. Many researches have focused the reconstruction of buildings that were modified by human actions, as wars or demolitions, or by natural causes as earthquakes or decay. Many buildings, destroyed or reshaped from the second half of the 19th century have been photographed before they vanished; when no drawing or document are available, the memory of the architecture layout of these buildings is entrusted to few period photos. Digital representation makes the reconstruction of gone buildings from period photos possible. Descriptive Geometry provides the conceptual and oper…
A New Technique for Coronaplasty in Penile Reconstruction.
2018
Abstract Background The coronaplasty is an important step of the phalloplasty procedure as it creates a prominent coronal ridge and a constricted coronal sulcus, resulting in the transformation of a regular skin flap into a flap resembling a circumcised penis. Aim The aim of this article is to describe our new coronaplasty technique that exploits opposing contracting forces of 2 different skin grafts to hold the shape of a thick, distally based skin flap, resulting in a natural looking neo-phallus. Methods A distally based flap is raised at the junction of the middle and distal thirds of the neo-phallus. The dissection continues until adequate mobilization is obtained, so the flap can stand…