scholarly journals Passive single-station techniques applied for dynamic characterization of reinforced concrete buildings

Rivista Tema ◽  
2020 ◽  
Vol Vol.6 (2020) (N. 1) ◽  
Author(s):  
Davide Prati ◽  
Lorenzo Badini ◽  
Giovanni Mochi ◽  
Silvia Castellaro ◽  
Annarita Ferrante
Keyword(s):  
Dynamic Characterization ◽  
Concrete Frame ◽  
Non Invasive ◽  
Combined Use ◽  
Single Station ◽  
Frame Buildings ◽  
The One

This work aims to better understand and improve the dynamic characterization of concrete frame buildings through the combined use of finite element modeling and applied seismology. The behavior of the FEM model is compared with values obtained directly in situ through non-invasive tests based on a sensor capable of detecting the seismic microtremor and provide direct information in terms of oscillation periods and displacements. The case study structure was measured using a seismometer, and, at the same time, modeled using SAP2000. By starting from extremely different initial data, multiple variations were made to the model to produce an increase in frequency, aligning it with the one detected instrumentally.

Dynamic characterization of column flotation process laboratory case study

1999 ◽  
Vol 12 (11) ◽  
pp. 1339-1346 ◽  
Author(s):  
T. Carvalho ◽  
F. Durão ◽  
C. Fernandes
Keyword(s):  
Column Flotation ◽  
Dynamic Characterization ◽  
Flotation Process

scholarly journals Brightly Colored to Stay in the Dark. Revealing of the Polychromy of the Lot Sarcophagus in the Catacomb of San Sebastiano in Rome

Heritage ◽  
2020 ◽  
Vol 3 (3) ◽  
pp. 858-874
Author(s):  
Susanna Bracci ◽  
Donata Magrini ◽  
Rachele Manganelli del Fà ◽  
Oana Adriana Cuzman ◽  
Barbara Mazzei
Keyword(s):  
Late Antiquity ◽  
3D Model ◽  
Non Invasive ◽  
Naked Eye ◽  
Executive Process ◽  
Different Types ◽  
Yellow Ochre ◽  
Invasive Techniques

The Lot Sarcophagus is one of the most relevant funerary sculptures of late antiquity (mid-4th century AC). Some of the remarkable aspects are the following (i) it is still preserved in situ; (ii) most of the carved scenes are rarities or unicum; (iii) not all the sculpture work has been completed, which allows us to analyse the executive process; (iv) many traces of polychromy have remained. This paper is focused on the characterization of the residual polychromy by using in-situ non-invasive techniques. Furthermore, few micro samples were taken, to be analysed in laboratory to study the composition of some deposits and to define if a preparatory layer was present under the coloured layer. The data showed that the very rich polychromy of the Lot Sarcophagus was made of Egyptian blue, yellow ochre, and three different types of red: two inorganics (red ochre and cinnabar), and one organic-based (madder lake). Furthermore, some decorations, completely vanished and no longer visible to the naked eye, have been rediscovered, also providing details on the construction phases. During the project, the 3D model of the sarcophagus was acquired, which afterwards was used to map the results of the diagnostic campaign.

scholarly journals A One-Pot Synthesis and Characterization of Antibacterial Silver Nanoparticle–Cellulose Film

Polymers ◽  
2020 ◽  
Vol 12 (2) ◽  
pp. 440 ◽  
Author(s):  
Qi-Yuan Chen ◽  
Sheng-Ling Xiao ◽  
Sheldon Q. Shi ◽  
Li-Ping Cai
Keyword(s):  
Composite Film ◽  
Food Packaging ◽  
Antibacterial Activities ◽  
Light Transmittance ◽  
Ag Nps ◽  
One Pot ◽  
One Pot Synthesis ◽  
The One

Using N,N-dimethylacetamide (DMAc) as a reducing agent in the presence of PVP-K30, the stable silver nanoparticles (Ag-NPs) solution was prepared by a convenient method for the in situ reduction of silver nitrate. The cellulose–Ag-NPs composite film (CANF) was cast in the same container using lithium chloride (LiCl) giving the Ag-NPs-PVP/DMAc solution cellulose solubility as well as γ-mercaptopropyltrimethoxysilane (MPTS) to couple Ag-NPs and cellulose. The results showed that the Ag-NPs were uniformly dispersed in solution, and the solution had strong antibacterial activities. It was found that the one-pot synthesis allowed the growth of and cross-linking with cellulose processes of Ag-NPs conducted simultaneously. Approximately 61% of Ag-NPs was successfully loaded in CANF, and Ag-NPs were uniformly dispersed in the surface and internal of the composite film. The composite film exhibited good tensile properties (tensile strength could reach up to 86.4 MPa), transparency (light transmittance exceeds 70%), thermal stability, and remarkable antibacterial activities. The sterilization effect of CANF0.04 against Staphylococcus aureus and Escherichia coli exceed 99.9%. Due to low residual LiCl/DMAc and low diffusion of Ag-NPs, the composite film may have potential for applications in food packaging and bacterial barrier.

Characterization of Nitrided Gate Oxide Formed by RTP for SiC MOSFET Application

2011 ◽  
Vol 324 ◽  
pp. 221-224 ◽  
Author(s):  
Aurore Constant ◽  
Philippe Godignon
Keyword(s):  
Gate Oxide ◽  
Breakdown Field ◽  
Gate Oxides ◽  
Furnace Process ◽  
Surface Pretreatment ◽  
Channel Mobility ◽  
Conventional Furnace ◽  
The One

Gate oxides for SiC lateral MOSFETs have been formed in N2O by rapid thermal processing (RTP) as an alternative to the conventional furnace process. This innovative oxidation method has not only the advantage to significantly reduce the thermal budget compared to a standard oxidation, but also to produce oxide layers with quality comparable to the one grown in a conventional furnace. Moreover, a significant improvement of the oxide quality and MOSFET performance is observed when performing in-situ a H2 anneal prior to oxidation as surface pretreatment. The channel mobility and the breakdown field of the gate oxide are considerably increased.

Synthesis and Characterization of Nanoscale CeO2 Catalyst for deNOx

2005 ◽  
Vol 23 ◽  
pp. 95-98 ◽  
Author(s):  
S. Kawi ◽  
Y.P. Tang ◽  
K. Hidajat ◽  
L.E. Yu
Keyword(s):  
Water Vapor ◽  
Catalytic Reduction ◽  
Precipitation Method ◽  
Synthesis And Characterization ◽  
In Situ Xrd ◽  
Surface Areas ◽  
Rich Condition ◽  
The One

Hydrothermal and precipitation methods have been applied to synthesize nanoscale CeO2 catalysts for selective catalytic reduction of NO with hydrocarbon under oxygen-rich condition. The former procedure has the advantage of enhancing the hydrothermal stability of nanomaterial. BET results show that their surface areas are about 30-80 m2/g. Based on TEM results, hydrothermally prepared CeO2 shows very uniform grain shaped particles with size around 10-20 nanometers. Its thermal stability up to 1200°C has been confirmed by in-situ XRD. Furthermore, deNOx reaction with propene as reducing agent in the presence of 5% oxygen has been carried out to compare catalysts prepared by the above two methods. Results show that hydrothermally prepared catalyst is more active than the one prepared by precipitation method. The latter one lost half of its activity in the presence of 5% water vapor, while the former one could stand up to 10% water vapor in the gas mixture without losing much activity.

Static and Dynamic Characterization of a Tight Reservoir- A Case-Study from Onshore Abu Dhabi Field

2019 ◽  
Author(s):  
Praveen Agnihotri ◽  
Vikram Pandey ◽  
Parmanand Thakur ◽  
Maisoon Al Mansoori ◽  
Michel Rebelle ◽  
...  
Keyword(s):  
Abu Dhabi ◽  
Dynamic Characterization ◽  
Tight Reservoir

Quickest Change Point Detection in Shape Inspection of Additively Manufactured Parts Under a Multi-Resolution Framework

2020 ◽  
Author(s):  
Yu Jin ◽  
Haitao Liao ◽  
Harry Pierson
Keyword(s):  
Point Cloud ◽  
Geometric Error ◽  
Change Point Detection ◽  
Layer By Layer ◽  
Shape Inspection ◽  
The One ◽  
Alignment Errors ◽  
Point Detection

Abstract In-situ layer-by-layer inspection is essential to achieving the full capability and advantages of additive manufacturing in producing complex geometries. The shape of each inspected layer can be described by a 2D point cloud obtained by slicing a thin layer of 3D point cloud acquired from 3D scanning. In practice, a scanned shape must be aligned with the corresponding base-truth CAD model before evaluating its geometric accuracy. Indeed, the observed geometric error is attributed to systematic, random, and alignment errors, where the systematic error is the one that triggers an alarm of system anomalies. In this work, a quickest change detection (QCD) algorithm is applied under a multi-resolution alignment and inspection framework 1) to differentiate errors from different error sources, and 2) to identify the layer where the earliest systematic deviation distribution changes during the printing process. Numerical experiments and a case study on a human heart are conducted to illustrate the performance of the proposed method in detecting layer-wise geometric error.

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