1,711 research outputs found
Dinamica degli "avalanching glaciers": il caso del seracco della Punta S. Matteo (Ghiacciaio dei Forni, Valtellina, Italia)
No full textAvalanching glaciers may be affected by periodic or occasional falls of ice (by breaking-off mechanism) giving rise to tragic events. These events have been rising the interest in the instability of avalanching glaciers. This contribution comes into this context. In summer 2003 a big fracture was observed on the North wall of Punta S. Matteo (Forni Glacier, Ortles-Cevedale Group, Italy). As this phenomenon developed a big unstable ice-mass, starting form May 2005, it was decided to survey Monte S. Matteo avalanching glacier (whose fall could involve the West sector of Forni Glacier thus representing an actual hazard for climbers, tourists, skiers and trekkers). The monitoring campaign consisted in collecting photographs (from May 2005 to March 2007) and in surveying the ice mass by total station (from July 2005 to November 2005). In addition, in May 2005 a laser scanner surveys was performed. The collected photographs made it possible to draw the evolution of this unstable ice-mass. Data acquired with total station permitted to calculate displacement, velocities and flow direction of the unstable ice-mass. The laser scanner survey permitted to calculate the volume of the unstable ice-mass. Furthermore the role of air temperature conditions in the ice-mass evolution was also investigated
Innovative and efficient data census on a cloud based digital twin provided by mobile mapping.
No full textThe article introduces the use of modern indoor mobile mapping systems (iMMS) equipped with a high resolution photographic camera, for the realization of asset acquisition campaigns of large building sites and for the generation of Digital Twins. The mapping project of a large part of the social housing real estate of the Municipality of Milan is taken as an example. The technical specifications and management methods of the 3D measurement and photographic acquisition processes in the field and the processing workflow, quality testing/certification and way to share on the cloud the Digital Twins are described
Recent evolution of the Punta San Matteo serac (Ortles-Cevedale Group, Italian Alps)
No full textThis paper summarizes the main results of surveys carried out on the Punta San Matteo serac (Ortles-Cevedale Group, Italy). The monitoring campaigns mainly consisted in surveying the serac with a Total Station (over the period from July 2005 to November 2005) and with a laser scanner. The displacements of the unstable ice mass (about 12 m) and its geometry and volume (about 560,000 m') have been calculated. In addition several photographs collected during the field campaigns made it possible to describe the evolution of this unstable ice mass and recorded its partial collapse and gradual breaking into tiny parts. The air temperature trend was also evaluated; the serac displacements resulted not strongly correlated with temperature evolution and the main falling events occurred in the autumn and not in summer when air temperature reached the highest peaks
Applicazioni del Laser Scanner terrestre a temi geologico-tecnici
No full textLaser scanner is an electronic instrument capable to survey the three-dimensional geometry of an object through a laser pulse measuring the distance between the laser head and the objects surface. Accuracy, acquisition time and range varies between several commercial products. Short range (up to 50-70 m) scanners can survey in few minutes at high resolution (ca. ± 2 mm), while long range scanners (up to 2000 m) can provide a decimetric accuracy and need more acquisition time. Laser scanner has the advantage that doesn’t need passive corner reflector on the object but on the other hand the measure accuracy could be dependent on the surface characteristics (material, dielectric constant, etc.). The laser scanner output is a three-dimensional cloud of points colored by reflectance values. Both the cloud of point and the derived mesh model can be textured using a external digital images; the final result is photorealistic model of the object completely measurable. Terrestrial laser scanner technology (hardware and software) is in continues developing and several application are related to the geological survey field of application. In particular laser scanner was applied for geo-mechanical analyses, rock fall monitoring, tunnel and cave survey, glacier monitoring. Further development are planned to simplified the usage and analyses of laser data for geologist trough user friendly software tool
A Moving 3D Laser Scanner for Automated Underbridge Inspection
No full textRecent researches have proven that the underbridge geometry can be reconstructed by mounting a 3D laser scanner on a motorized cart travelling on a walkway located under the bridge. The walkway is moved by a truck and the accuracy of the bridge model depends on the accuracy of the trajectory of the scanning head with respect to a fixed reference system. In this paper, we describe a vision-based measurement system that can be used to identify the relative motion of the cart that moves the 3D laser scanner with respect to the walkway. The orientation of the walkway with respect to the bridge is determined using inclinometers and a camera that detect the position of a laser spot, while the position of the truck with respect to the bridge is measured using a conventional odometer. The accuracy of the proposed system was initially evaluated by numerical simulations and successively verified by experiments in laboratory conditions. The complete system has then been tested by comparing the geometry of buildings reconstructed using the proposed system with the geometry obtained with a static scan. Results showed that the error is less than 6 mm; given the satisfying quality of the point clouds obtained, it is also possible to detect small defects on the surface
TUTELA DEL LAVORO E LIBERTA' D'IMPRESA NEI PROCESSI DI ESTERNALIZZAZIONE
No full textL’elaborato analizza le conseguenze lavoristiche della successione fra imprenditori, muovendo da una ricognizione delle varie tipologie di esternalizzazione con le relative esigenze e principali criticità.
L’indagine si concentra in primo luogo sul trasferimento d’azienda, esaminando la normativa e la giurisprudenza europee per passare poi alla disciplina di diritto interno, alle procedure sindacali e a uno specifico focus sul trasferimento delle aziende in crisi.
Successivamente l’autore si sofferma sull’appalto, prendendone in particolare considerazione gli indici di genuinità, i criteri di distinzione dalla somministrazione illecita di manodopera e la tutela delle maestranze in caso di avvicendamento fra imprese.
Da ultimo, la ricerca approfondisce le c.d. “clausole sociali”, sia di prima che di seconda generazione, valutandone la compatibilità con il diritto eurounitario e con la costituzione nonché riflettendo sui possibili rimedi in caso di loro violazione.The author analyzes the labour consequences of the succession between entrepreneurs, starting from a recognition of the various types of outsourcing with the related needs and main critical issues.
The survey focuses primarily on the transfer of businesses, examining European legislation and case-law and then moving on to internal legislation, trade union procedures and a specific focus on the transfer of companies in crisis.
The author then dwells on the contract, taking into account in particular the indications of authenticity, the criteria of distinction from the illicit administration of labour and the protection of workers in the event of turnover between companies.
Finally, the research deepens the "social clauses", both first and second generation, assessing their compatibility with European law and with the constitution and reflecting on possible remedies in case of their violation
Monitoraggio e verifica costruttiva (as built) di grattacieli e strutture di ingegneria civile a prevalente sviluppo verticale
No full textDinamica degli "avanching glaciers": il caso del seracco della Punta S. Matteo (Ghiacciaio dei Forni, Valtellina, Italia)
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