Search results for "analytical approach"
showing 7 items of 7 documents
Portable Spectroscopic Techniques for the Non-invasive Identification of two historical yellow pigments: Applications and Practical Challenges
2022
Abstract Decades of technological advances in instrumental analysis have transformed many techniques from laboratory in portable analytical tools with increasing their applicability in situ to the study of cultural heritage. It is known that the painting realisation varies from artist to artist, and the identification of the pigments provides a decisive contribution to trace their authenticity and to support an appropriate restoration work. However, in some cases, due to the complexity of painting composition, it is difficult to distinguish between pigments having a similar chemical composition and colour. Here, a systematic study through combined use of portable non-invasive spectroscopic …
Polychrome wood sculpture depicting The Madonna del Soccorso or della Mazza from the Archdiocese of Palermo: an integrated analytical approach for th…
2018
In this study the Madonna del Soccorsoo della Mazza wooden sculpture has been analysed by an interdisciplinary and integrated approach. The polychrome sculpture, dating back to the 18thcentury, comes from the church of the Madonna del Soccorso or della Mazza (1604) situated in Via Maqueda, in Palermo and it was placed on the main recess of the altar. All steps of the conservation project, from the preliminary study to the choice of materials and the restoration procedures have been accompanied and supported by diagnostic and scientific analysis. In order to evaluate the state of conservation of the sculpture and the technique employed to construct the support, computer tomography study was …
Investigation of archaeological amphorae from the Egadi battles
2022
Abstract Archaeological ceramics are considered one of the most important sources of both technological and chronological information. Here, the investigation of some archaeological underwater amphorae from the Egadi’s Battle, that decided the end of the First Punic War (241 B.C.), is reported. X-ray Diffraction (XRD), X-ray Fluorescence (XRF), petrography, and Thermoluminescence (TL) were used to determine the composition of the amphorae and to evaluate the compatibly of their age with the above Battle. Considering the historical importance of the act and the well-defined historical collocation these amphorae represent an interesting archaeometric case study.
Computing bi-tangents for transmission belts
2020
In this note, we determine the bi-tangents of two rotated ellipses, and we compute the coordinates of their points of tangency. For these purposes, we develop two approaches. The first one is an analytical approach in which we compute analytically the equations of the bi-tangents. This approach is valid only for some cases. The second one is geometrical and is based on the determination of the normal vector to the tangent line. This approach turns out to be more robust than the first one and is valid for any configuration of ellipses.
Analitical deriving of the field capacity through soil bundle model
2015
The concept of field capacity as soil hydraulic parameter is widely used in many hydrological applications. Althought its recurring usage, its definition is not univocal. Traditionally, field capacity has been related to the amount of water that remains in the soil after the excess water has drained away and the water downward movement experiences a significant decresase. Quantifying the drainage of excess of water may be vague and several definitions, often subjective, have been proposed. These definitions are based on fixed thresholds either of time, pressure, or flux to which the field capacity condition is associated. The fluxbased definition identifies the field capacity as the soil m…
Capturing learning in classroom interaction in mathematics: Methodological considerations
2015
International audience; This paper discusses issues of how to transcribe and analyze video-recordings when studying learning in small group work in mathematics. Since bodily features of interaction and the use of artefacts play important roles in mathematical reasoning, a multimodal approach to transcribing is necessary. Thus, the theoretical grounding for transcriptions has to be in accord with the perspective on learning adopted in the analysis. In the paper, the principles for studying what Radford (2000) refers to as knowledge objectification processes when learning mathematics will be discussed.
Analytical approach for the problems of dynamics and stability of a moving web
2015
Problems of dynamics and stability of a moving web, modelled as an elastic rod or string, and axially travelling between rollers (supports) at a constant velocity, are studied using analytical approaches. Transverse, longitudinal and torsional vibrations of the moving web are described by a hyperbolic second-order partial differential equation, corresponding to the string and rod models. It is shown that in the framework of a quasi-static eigenvalue analysis, for these models, the critical point cannot be unstable. The critical velocities of one-dimensional webs, and the arising non-trivial solution of free vibrations, are studied analytically. The dynamical analysis is then extended into t…