Search results for "scanning"

Rilievi laser scanner con tecniche di registrazione in situ: il sistema Topcon GLS2000 per il rilievo di siti archeologici

Il lavoro svolto presenta i risultati ottenuti durante una campagna di rilievi laser scanner in ambito archeologico effettuata utilizzando il sistema GLS2000 della Topcon. Le attività di rilievo sono state condotte per la documentazione e ricostruzione tridimensionale della Domus romana all’interno del Parco archeologico di Lilibeo a Marsala. Lo scopo del lavoro è stato quello di utilizzare e verificare le tecniche di registrazione in situ impiegando, in particolare, il metodo della poligonale.

Integration of terrestrial laser scanning and UAV-SFM technique to generate a detailed 3D textured model of a heritage building

2020

The digital twin is among the Top 10 of the strategic technological trends for the period 2007-2019, and it represents a powerful tool for the conservation and enhancement of cultural heritage. It reproduces with "precision" a physical asset, thus allowing to investigate its structure and to analyze the deformations that occur over the years. Various techniques have been introduced to obtain high-resolution 3D models. Among these, the Terrestrial Laser Scanner (TLS) is widely recognized as the gold standard to generate accurate 3D metric reconstructions. TLS allows acquiring a lot of data (point cloud) in a fast way, being not in physical contact with the objects of investigation. By integr…

Elaboración de modelos 3D de diferentes morfologías y escalas utilizando técnicas Structure-from-Motion y fotografías terrestres

2016

En este trabajo se evalúan los métodos de foto-reconstrucción automatizada basados en el uso conjunto de las técnicas Structure from Motion (SfM) y Multi-View Stereo (MVS) para medir, monitorizar y cuantificar la dinámica de tres formas geomorfológicas: i) el glaciar rocoso del Corral del Veleta (Granada, España), ii) un paisaje de cárcavas de tipo calanchi (Sicilia, Italia) y ii) cinco pequeñas cabeceras de cárcava (Cáceres, España). Se incluyen en este trabajo los resultados sobre la precisión, utilidad y aplicabilidad de estas técnicas. Para la cuantificación de la precisión se utilizan el error cuadrático medio (RMSE) de los puntos de control que se emplean en la georreferenciación y la…

The Latomiae of Syracuse: A Geotechnical Mapping Through Rock Reflectivity

2014

The archeological site of the Latomia del Paradiso (Syracuse) is endangered by severe instability phenomena due to the shape of walls and underground excava-tion related with the poor mechanical characteristics of the weathered and wet rock. The failure of huge blocks from the ceiling of the underground areas and the detaching of rock "flakes" from the walls surface make the geotechnical zon-ing particularly complex. the zoning is based on the characteristics of the rock wall surface that, in first approximation, can be distinguished in regularized sur-faces because of mining , and in irregular surfaces characterized by fracture prop-agation. The elaboration of reflectivity values obtained …

Corneal thickness differences between type 2 diabetes and non-diabetes subjects during preoperative laser surgery examination

2016

Aims To evaluate the differences in corneal thickness between type 2 diabetes subjects with HbA1c under 7.0% and non-diabetes subjects during their preoperative laser surgery examinations. Methods The mean of five consecutive corneal thickness measurements at the central and mid-peripheral cornea was obtained by means of noncontact scanning-slit corneal topography (Orbscan Topography System II; Orbscan, Inc., Salt Lake City, UT, USA) in 35 myopic non-insulin dependent type 2 diabetes subjects (17 males and 18 females) and 48 healthy myopic controls (23 males and 25 females). Results The corneal thickness values at the central and mid-peripheral cornea were significantly higher in the diabet…

High Reliability Laser Tracking System

2004

A simple and long-life laser beam steering device has been developed. Continuous operation for low angle steering is achieved through the use of a damped resonant scanner. The system exhibits a flat bandwidth up to 100 Hz and is suited for tracking vibrating objects or in random motion around a fixed point. Applications in the field of laser tracking and beam stabilization are proposed and discussed.

Detection of archaeological forgeries of Iberian lead plates using nanoelectrochemical techniques. The lot of fake plates from Bugarra (Spain)

2014

Identification of forgeries is of considerable interest in studies of archaeological signariums and written Iberian artifacts, elements of capital importance for the knowledge of that culture, because there are many Iberian inscribed lead plate counterfeits circulating in the market and among many museum funds. A case study of identification of forgeries of archaeological lead using voltammetry of microparticles (VMP) and scanning electrochemical microscopy (SECM), aided by conventional optical microscopy and scanning electron microscopy (SEM/EDX) is described. The electrochemical methods are essentially non-invasive so can be applied to samples of nanoscopic size. Application to the authen…

Atomic-scale magnetic domain walls in quasi-one-dimensional Fe nanostripes.

2001

Fe nanostripes on W(110) are investigated by Kerr magnetometry and spin-polarized scanning tunneling microscopy (SP-STM). An Arrhenius law is observed for the temperature dependent magnetic susceptibility indicating a one-dimensional magnetic behavior. The activation energy for creating antiparallel spin blocks indicates extremely narrow domain walls with a width on a length scale of the lattice constant. This is confirmed by imaging the domain wall by SP-STM. This information allows the quantification of the exchange stiffness and the anisotropy constant.

Small Angle Neutron Scattering, X-ray Diffraction, Differential Scanning Calorimetry, and Thermogravimetry Studies to Characterize the Properties of …

2009

Nanocomposites based on laponite RD and (ethylene oxide)98(propylene oxide)67(ethylene oxide)98 (F127)triblock copolymer or poly(ethylene) glycol 2000 (PEG2000) were prepared by using the melting method. Small-angle neutron scattering and the X-ray diffraction experiments provided insights into the organization of the laponite RD dispersed in the macromolecular matrix over a wide length scale. SANS data analysis by means of a fractal law evidenced the formation of clusters of laponite RD at long correlation distance. The single laponite RD particles and the lamellar structure of F127 were described in the shorter length scale. Finally, the crystalline structure of the macromolecule was obse…

Moir\'e-enabled topological superconductivity

2020

The search for artificial topological superconductivity has been limited by the stringent conditions required for its emergence. As exemplified by the recent discoveries of various correlated electronic states in twisted van der Waals materials, moir\'e patterns can act as a powerful knob to create artificial electronic structures. Here, we demonstrate that a moir\'e pattern between a van der Waals superconductor and a monolayer ferromagnet creates a periodic potential modulation that enables the realization of a topological superconducting state that would not be accessible in the absence of the moir\'e. The magnetic moir\'e pattern gives rise to Yu-Shiba-Rusinov minibands and periodic mod…