Search results for " Tom"

Recent progress in electrical impedance tomography

2003

We consider the inverse problem of finding cavities within some body from electrostatic measurements on the boundary. By a cavity we understand any object with a different electrical conductivity from the background material of the body. We survey two algorithms for solving this inverse problem, namely the factorization method and a MUSIC-type algorithm. In particular, we present a number of numerical results to highlight the potential and the limitations of these two methods.

Jacobian of solutions to the conductivity equation in limited view

2022

Abstract The aim of hybrid inverse problems such as Acousto-Electric Tomography or Current Density Imaging is the reconstruction of the electrical conductivity in a domain that can only be accessed from its exterior. In the inversion procedure, the solutions to the conductivity equation play a central role. In particular, it is important that the Jacobian of the solutions is non-vanishing. In the present paper we address a two-dimensional limited view setting, where only a part of the boundary of the domain can be controlled by a non-zero Dirichlet condition, while on the remaining boundary there is a zero Dirichlet condition. For this setting, we propose sufficient conditions on the bounda…

Integrated geophysical survey in the archaeological site of Himera (Northern Sicily)

2005

X-ray computed tomography investigations of Cucuteni ceramic statuettes:

2013

Deciphering the internal structure of prehistoric artefacts can provide spectacular insights that might help us understand the people who made them. In order to preserve the integrity of these relics of past civilisations, it is desirable to make such investigations using non-destructive techniques. Recent decades have witnessed a growth in the X-ray computed tomography (CT) applications in the study of cultural heritage objects. This paper presents and discusses tomographic investigations of two Cucuteni ceramic statuettes discovered in Romania. The study was made with a CT device specially designed for archaeometric applications.

Joint interpretation of electrical and seismic data aimed at modelling the foundation soils of the Maredolce monumental complex in Palermo (Italy)

2020

The monumental complex of Maredolce (Palermo) includes an Arab-Norman castle that stands on the banks of an artificial lake carved out of the calcarenitic rock that rests on impermeable clays. The lake was originally filled with water, thanks to the channelling of a spring. Over time, the lowering of the water table and the high hydraulic permeability of the calcarenites have caused the lake to dry up. A project to renovate the monumental complex has recently been launched. It also provides the study of a possible restoration of the original conditions of the lake. To this end, a multidisciplinary geophysical study was carried out to investigate the geotechnical conditions of permeability o…

Seismic and non‐invasive geophysical surveys for the renovation project of Branciforte Palace in Palermo

2020

The renovation project of the historic Branciforte Palace (16th–17th century) in Palermo (Italy) was owned by the Banco di Sicilia Foundation, with the aim for it to become a multi-purpose centre for the promotion of exhibitions and cultural events. In the context of the restoration work, a multi-methodological and non-invasive geophysical study has been carried out. The seismic characterization of the foundation soils was obtained by means of joint interpretations of a vertical seismic profile (VSP), multichannel analysis of surface waves (MASW) and horizontal to vertical spectral ratio (HVSR) microtremor analysis. The mutually constrained inversion of seismic surveys carried out with diff…

The Protohistoric sword from Le Gué-de-Velluire (Vendée, France): a pasticcio's history unveiled by archaeometrical research

2020

International audience; The Gué-de-Velluire sword (Vendée, France) is part of the Rochebrune collection collected during the 19 th and the 20 th centuries and now preserved in the Dobrée Museum in Nantes (Loire-Atlantique, France). The unusual shape of its hilt, its uncorroded rivets and the rather uncommon combination of a bronze grip with an iron blade made this sword an exceptional object. It has been depicted in a large number of papers since the 20 th century, but the question of its authenticity has hardly ever been tackled. New analyses performed with the support of the Dobrée Museum, the Arc'Antique laboratory and Ghent University delivered new data enabling us to discuss this delic…

An execution in medieval Sicily: Computerised tomography scan analysis and 3D reconstruction of an ancient forensic context

2019

The bioarchaeological and forensic approach is increasingly applied in the study of funerary contexts in archaeology. Here, we present a case of an atypical medieval burial recently discovered in Piazza Armerina (Sicily), in which the integrated use of traditional bioarchaeological and forensic anthropology methods was crucial. The skeleton was lying in a prone position and was characterised by a peculiar injury pattern. We recorded six clear stab wound marks on the posterior surface of the sternum. The use of computerised tomography scan and 3D modelling techniques has made it possible to obtain a reliable reconstruction of the cause and modality of death, pointing to the execution of the …

An Overview of Geophysical Techniques and Their Potential Suitability for Archaeological Studies

2023

The need to study, protect, and conserve archaeological heritage has enhanced the application of geophysical techniques as non-invasive and reliable tools to investigate fragile and valuable assets. This review presents the most popular geophysical techniques suitable for archaeogeophysical investigations, namely, magnetometry, ground penetrating radar, and electrical resistivity tomography, together with a series of multiparametric measures taken from aerial platforms (UAS). For each method, we recall the basic physical principles, illustrate the operative procedures for field investigation, and provide indications about data processing and modeling. We propose a flowchart to address relia…

An integrated program of geophysical survey, coring, and test excavations to study a 4th millennium bc-cal ditch at Alt del Punxó (Muro de L’alcoi, A…

2008

The potentially long and interesting archaeological sequence revealed by systematic survey at the site of Alt Del Punxó (Muro de l’Alcoi, Alacant) was the basis for initiating a study of the locality’s subsurface structures using new methods of remote sensing. Geophysical survey (magnetometry and tomography) and systematic augering revealed buried structures, including monumental earthworks, and guided subsequent excavations to collect more detailed data about the nature and age of these prehistoric features. The information recovered, including new radiocarbon dates, offers a new perspective on the organization of prehistoric populations in this region of south-central Valencia since the b…