Search results for "displacements"
showing 10 items of 15 documents
Toward a Comprehensive Dam Monitoring: On-Site and Remote-Retrieved Forcing Factors and Resulting Displacements (GNSS and PS–InSAR)
2021
Many factors can influence the displacements of a dam, including water level variability and environmental temperatures, in addition to the dam composition. In this work, optical-based classification, thermal diachronic analysis, and a quasi-PS (Persistent Scatter) Interferometric SAR technique have been applied to determine both forcing factors and resulting displacements of the crest of the Castello dam (South Italy) over a one-year time period. The dataset includes Sentinel-1A images acquired in Interferometric Wide swath mode using the Terrain Observation with Progressive Scans SAR (TOPSAR); Landsat 8 Thermal Infrared Sensor (TIRS) thermal images, and Global Navigation Satellite System …
Molecular origin and hydration dependence of protein anharmonicity: an elastic neutron scattering study.
2010
Two main onsets of anharmonicity are present in protein dynamics. Neutron scattering on protein hydrated powders revealed a first onset at about 150 K and a second one at about 230 K (the so called dynamical transition). In order to assess the molecular origin of protein anharmonicity, we study different homomeric polypeptides by incoherent elastic neutron scattering, thus disentangling the contribution of different molecular groups in proteins. We show that methyl group rotations are the main contributors to the low temperature onset. Concerning the dynamical transition, we show that it also occurs in absence of side chains; however, the presence and mobility of side chains substantially i…
Investigating effects in GNSS station coordinate time series
2014
The vertical and horizontal displacements of the Earth can be measured to a high degree of precision using GNSS. Time series of Latvian GNSS station positions of both the EUPOS®-Riga and LatPos networks have been developed at the Institute of Geodesy and Geoinformation of the University of Latvia (LU GGI). In this study the main focus is made on the noise analysis of the obtained time series and site displacement identification. The results of time series have been analysed and distinctive behaviour of EUPOS®-Riga and LatPos station coordinate changes have been identified. The possible dependences of GNSS station coordinate distribution on EPN station problems, seismic activity of some area…
Dynamical properties of myoglobin in an ultraviscous water-glycerol solvent investigated with elastic neutron scattering and FTIR spectroscopy
2018
Abstract Proteins have distinctive dynamical properties, characterized by the fluctuations of protein molecules among the different minima of their energy landscape. These fluctuations, progressively activated for temperature values larger than ~180 K, lead to a steep increase in the temperature dependence of all measurable dynamical properties. This phenomenon is known as Protein Dynamical Transition and, in spite of the intense studies due to its importance in protein function and to the relation with the fascinating fundamental thermodynamics of complex systems, many aspects of it are not yet clearly understood. Among these, the relationship with the properties of the external solvent an…
Approximate Solution on Large Deflection of Glass Panels Subjected to Uniform Pressure
2015
The estimation of the deflection of glass panels under wind pressure is important in designing external facades of buildings. A direct method to compute the large deflections of glass panels under uniform loads such as wind pressure is presented. The model allows for derivation of the load-deflection response of square or rectangular multilayered glass panels subject to uniform loads. The boundary conditions examined are those of four-point discontinuous supports or continuous supports along the four sides. With some assumptions on bending and membrane action of flat glasses, simple analytical expressions were derived from the elastic theory. Viscoelastic effects for multilayered glass pane…
Finite Displacements and Corrotational Interfaces: Consistent formulation and Symmetry of the Stiffness Matrix
2017
Mechanical interfaces are theoretical and computational tools able to properly reproduce then progressive delamination of composite structures. Scientific literature is rich of interface models, mostly developed in small displacements, whereas a few of them assess the problem in a geometrically nonlinear setting. In the present paper interface formulation is rigorously developed in a geometrically nonlinear setting, and the relevant interface constitutive relations are defined in the local reference with normal and tangential axes to the middle surface in the current configuration. The interface is defined as a zero thickness layer with tractions acting between the two connected surfaces. M…
Neutron Scattering Reveals Enhanced Protein Dynamics in Concanavalin A Amyloid Fibrils
2012
Protein aggregation is one of the most challenging topics in life sciences, and it is implicated in several human pathologies. The nature and the role of toxic species is highly debated, with amyloid fibrils being among the most relevant species for their peculiar structural and functional properties. Protein dynamics and in particular the ability to fluctuate through a large number of conformational substates are closely related to protein function. This Letter focuses on amyloid fibril dynamics, and, to our knowledge, it is the first neutron scattering study on a protein (Concanavalin A) isolated in its fibril state. Our results reveal enhanced atomic fluctuations in amyloid fibrils and i…
Reservoir monitoring using satellite SAR and GNSS: a case study in southern Italy
2018
Recently, it has been demonstrated that it is possible to relate water levels of a reservoir with its dam displacements. Water levels were determined via remote sensing, while dam displacements were measured via Global Navigation Satellite System (GNSS). Results have shown that displacements and water levels are correlated.Water levels at the Magazzolo reservoir in southern Italy were firstly retrieved using two remote sensing approaches: by visual matching between the reservoir shoreline and contour lines, and by evaluating the surface extent via unsupervised classification to estimate the water levels with an area/depth relation. Dam displacements were measured using GPS receivers on the …
STUDY OF NEW AUTOMOTIVE REAR SUSPENSION MECHANISM
2011
The paper presents firstly an introduction discussing: the problem’s statement emphasizing the actual problem of research of passenger car suspension to improve driving comfort and dynamic of the vehicle movement; aspects regarding the studies of car suspension mechanisms; the paper’s aims and objectives showing that a new configuration of suspension mechanism having in structure mobile frame and an actuator offering some important operational advantages is proposed. After this, the innovative concept is presented. The motions of mechanism elements and actuator and kinematic displacements are largely presented. The simulation using modern software (MSC Patran 2007, MD R2 Nastran and MSC ADA…
Monitoring Water Surface and Level of a Reservoir Using Different Remote Sensing Approaches and Comparison with Dam Displacements Evaluated via GNSS
2018
Remote sensing allowed monitoring the reservoir water level by estimating its surface extension. Surface extension has been estimated using different approaches, employing both optical (Landsat 5 TM, Landsat 7 ETM+ SLC-Off, Landsat 8 OLI-TIRS and ASTER images) and Synthetic Aperture Radar (SAR) images (Cosmo SkyMed and TerraSAR-X). Images were characterized by different acquisition modes, geometric and spectral resolutions, allowing the evaluation of alternative and/or complementary techniques. For each kind of image, two techniques have been tested: The first based on an unsupervised classification and suitable to automate the process, the second based on visual matching with contour lines…