PHOTOGRAMMETRY DRIVEN TOOLS TO SUPPORT THE RESTORATION OF OPEN-AIR BRONZE SURFACES OF SCULPTURES: AN INTEGRATED SOLUTION STARTING FROM THE EXPERIENCE OF THE NEPTUNE FOUNTAIN IN BOLOGNA

Checking the irreversible process of clean-up is a delicate task that requires a work of synthesis between theoretical knowledge and practical experience, to define an effective operating protocol on a limited patch area to be extended later to the entire artefact's surface. In this paper, we present a new, quick, semi-automated 3D photogrammetry-based solution to support restorers in the open-air bronze artwork cleaning from corrosion and weathering decay. The solution allows the conservators to assess in real time and with a high level of fidelity in colour and shape, the 'surfaces' to be cleaned before, during and after the clear-out treatment. The solution besides allows an effective and valuable support tool for restorers to identify the original layer of the bronze surface, developed and validated during the ongoing restoration of the Neptune Fountain in Bologna

Natural based products for cleaning copper and copper alloys artefacts

Copper alloys objects can deteriorate their conservation state through irreversible corrosion. Since in the cultural heritage field every artefact is unique and any loss irreplaceable, solutions for conservation are needed. Hence, there is the necessity to stop the corrosion process with a suitable cleaning and conservation process to avoid further degradation processes without changing its morphological aspect. Chelating solutions are commonly used in chemical cleaning, mainly sodium salts of ethylenediaminetetraacetic acid (EDTA). However, it is resistant to water purification procedures and is not biodegradable. The goal of this study was to see if applying an ecologically friendly chelating agent as an alternative to EDTA cleaning procedures for cultural heritage was suitable. In this study were chosen six natural-based chelators that could be a new green non-toxic alternative to EDTA in corrosion-inhibiting properties. They were tested for cleaning copper artefacts exposed to atmospheric environment in polluted areas. The study considered four amino acids, a glucoheptonate (CSA) and an industrial green chelator (GLDA). The effectiveness was tested on corrosion copper compounds and on laboratory corroded copper sheets. Finally, the cleaning efficacy was tested on four Roman coins and a modern copper painting. To define the cleaning efficacy, surface analytical investigations have been carried out by means ICP-OES, UV-VIS, µ-Raman, spectro-colorimetry, XRD and FTIR. Among the amino acids, alanine was the most effective, showing an unaltered noble patina and a good effective copper recovery from corrosion patinas

Comparative study of protective coatings for the conservation of Urban Art

Contemporary mural paintings are complex artworks for several reasons, including the heterogeneity of the materials used to make them, and the different types of substrate on which the painting layers can be applied. Currently we are focused on a technical-scientific research aimed to solve the issues related to the long-term care and maintenance of murals, by evaluating the performance of several protective coatings applied on these artworks. This paper deals with a preliminary experimentation aimed to: (a) study the interaction of antigraffiti products on common synthetic paints; (b) test the effectiveness and efficiency of several commercial products used as antigraffiti; (c) define of the best procedure to remove vandalism spray from a coated surface, without damaging the underlying painting layers. Tests have been carried out on laboratory specimens and the performances of different antigraffiti agents have been evaluated by optical and electron microscope observations, as well as by colorimetric measurements

Lacuna e integrazione nel restauro dei metalli archeologici: oltre la ricomposizione, verso la restituzione dell\u2019opera. Riflessioni e proposte, tra teoria e prassi

The task of the conservator, in cooperation with the archaeologist, is to analyse archaeological material from an historical and technical standpoint in such a way that the act of conserving prior to presentation of an artefact is designed and executed for the specific artefact. This intervention must be carried out in a competent manner, i.e. the form and recognition must not be disrupted. Unfortunately, due to the corrosion of metal objects, artefacts change, which make the work of the conservator difficult. During instruction at the ISCR (Istituto Superiore per la Conservazione ed il Restauro), the possibilities for reconstructing complex metal artefacts in a collection, which shows signs of formal and aesthetic integrity, were analysed as examples. It involved filling the caesurae and defects in morphology and size. This work was aimed at restoring the integrity of the work on the formal and aesthetic side. The study also recapitulates the contribution in terms of the historical utility function of the studied objects and their technical properties

Conservare i murales outdoor: alcuni esempi romani.

Il tema della conservazione in situ di opere murali outdoor \ue8 al centro, negli ultimi tempi, di un accesso dibattito soprattutto in relazione al differente approccio da adottare a seconda che l\u2019opera sia un murale oppure un dipinto murale. Fino a pochi anni fa l\u2019interesse crescente per la conservazione della cosiddetta \u201cstreet art\u201d ha portato alla ricerca di nuove metodologie e alla sperimentazione di nuovi prodotti da applicare sulle opere al fine di garantirne la durabilit\ue0 nel tempo. Attualmente il restauratore/conservatore che si trova di fronte ad un\u2019opera di \u201cUrban Art\u201d deve adottare un approccio conservativo molto pi\uf9 cauto ponendosi alcune questioni preliminari legate alla reale necessit\ue0 di proteggere e salvare le opere di arte urbana realizzate da artisti che lavorano in ambienti esterni

Electronic commerce for competitiveness of food networks: The issue of trust

E-commerce and its potentials for efficiency in transactions offers important potentials for the competitiveness of food chains. However, existing e-commerce solutions lack trust generating elements to make ecommerce transactions trustworthy for food companies. To be able to exploit the potentials of e-commerce for efficiency and competitiveness in food chains, trust generation in electronic transaction environments is essential. This papers develops trust elements for electronic transactions in food chains. First, the hierarchy of trust elements based on expert judgments operating in agri-food chains was explored. Three categories of trust factors were elaborated, namely: \u201cshare of significances and motivations\u201d, \u201creliability and reputation\u201d, and \u201cintegration availability and non-opportunistic behaviour\u201d. Furthermore, within the above mentioned categories, six trust specific factors were identified. The Analytic Hierarchy Process technique was adopted to investigate and evaluate the relevance of the considered components. In this way it was possible to define a priority between the identified elements on their capacity to stimulate trust in B2B relations in a specific context. The hierarchical model defined in this way seems capable to assign a priority order to the elements inspire trust during e-trade relationship in the agrifood chains. Further investigations are needed to test the validity of the construct into a real business environment

Study of optical tag profile of the tag recognition measurement system in cultural heritage

This study exposes the process to identify the optimum optical tag profile to be used for monitoring the minimum relative displacement of two areas of the artwork. The purpose is to realize an efficient, precise, and accurate structural monitoring system with minimal invasiveness. In particular, it is designed to determine the enlargement of a crack on a fresco inside a closed environment, such as inside a church. Theoretical studies and measurements in a controlled environment are performed to identify the best mathematical distribution to be used as tags. The two small adhesive tags are the main components of the system, they are attached on the surface of the artwork and the acquisition of their images is performed through a high-resolution camera. An advanced least-squares fitting of quadratic curves and surfaces algorithms for the objective function are used to detect the relative distance between these optical tags. The appropriate parameters for monitoring potential cracks on cultural assets are determined with a fitting algorithm of an objective function. In this study, different bi-dimensional objective functions are considered to identify the best configuration