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The purpose of the present research was to compare the effect of different embedding and polishing procedures on the performances achievable with Fourier Transformed Infrared (FTIR) microscopy in Attenuated Total Reflection (ATR) mode. The attention was specifically focused on this technique since it is generally considered one of the most appropriate methods to analyze cross sections, thanks to the fact that the recorded spectra are similar to those collected in transmission mode. The research work was structured as a round robin among six different conservation and research laboratories. They were asked to embed fragments derived from the same area of a real sample following each one a different procedure. The performances of FTIR microscopy in ATR mode were evaluated on the different cross sections, considering the cross section morphology and the possible source of contamination. The cross sections were previously observed with optical microscopy, Environmental Scanning Electron Microscope (ESEM) and confocal microscopy. Three procedures were eventually selected, because they provided the best results in terms of both limiting the contamination of the embedding medium and achieving good contact with the ATR crystal. They were: a) embedding in KBr; b) cyclododecane pre-treatment before embedding in an organic resin and cutting of the sample; c) embedding in an organic resin and polishing with argon ion milling. These three procedures were finally compared and the weak points outlined, indicating where improvements could be made for further researches.

Frequency-dependent effects in railway traction power systems arise from the impedance of substation and locomotive line filters and the traction line. Harmonic noise from traction drives and substations can excite resonances and produce overcurrent or overvoltage conditions at critical points in the network. In this paper, the harmonic feeding impedances of a 3 kV DC traction system seen from the rectifier substation, locomotive drive converter and pantograph terminals are presented. Several substation and locomotive filters are considered with a frequency-dependent traction line. Resonances attributed to the substation filter, locomotive filter and traction line are separate and distinct, the line introducing poles and zeros in the audio frequency (AF) range which vary in frequency and magnitude with locomotive position. >

A generalization of the PWM (pulse width modulation) subharmonic method for controlling single-phase or three-phase multilevel voltage source inverters (VSIs) is considered. Three multilevel PWM techniques for VSI inverters are presented. An analytical expression of the spectral components of the output waveforms covering all the operating conditions is derived. The analysis is based on an extension of Bennet's method. The improvements in harmonic spectrum are pointed out, and several examples are presented which prove the validity of the multilevel modulation. Improvements in the harmonic contents were achieved due to the increased number of levels. >

The advantages of energy storage systems operating on electric power networks are well known, concerning with their capabilities of load levelling. As superconductivity technology improves and expa...

This paper describes how the issue of the modal rebalance has concentrated the attention of European countries on the standardization of the railway system to allow convoys to travel more simply around Europe. It came about as a result of the creation of international work groups, the realization of the European Railway Traffic Management System/European Traffic Control System (ERTMS/ETCS) and of the relative technical specifications of interoperability. The possibility of applying radar based technologies to ERTMS has been estimated for technologies that are able to improve the visibility of objects on the track and to bypass the geometric distortion problem in the most complete possible way. Moreover, the radar based technology concurs, if compared to the optical based devices that use cameras, to exceed the problems concerned in the reduction of visibility for atmospheric causes. The objective of this paper is to estimate the possibility to apply, in particular to the High Speed system characterized by a high speed rank and by a line architecture that is quite simple and linear, resorting to a simulation instrument which will concur, opportunely shaped with different scenes, to estimate if it could also be applied to different regimes of circulation.

The use of a constant inductance and resistance model for rail track impedance in traction power system fault transient studies gives rise to inaccuracies due to the actual frequency dependency of the line. In this paper, an accurate frequency-dependent track model for a third-rail metro railway is described in which the track feeding impedance is synthesized from the self and mutual impedances and represented by a discrete-component linear circuit network. The model is used to simulate current rise in a third-rail traction system short-circuit fault. Results are given for short and long track section feeding lengths and show significant differences compared with a constant-parameter track model. >

The authors analyze the validity of active filtering systems in the presence of DC drives. In these drive systems harmonics are generated by one or more choppers duly shifted out of phase. This means that the current ripple frequency of the first harmonic is generally constant and it is linked to the frequency of the carrier wave with which the chopper is modulated. Results obtained so far have shown the flexibility of such a filtering technique. The purpose of reducing filter weights and dimensions seems to be achieved through a nonexcessively complex system. >

This paper deals with the technological solutions currently adopted in Italy in order to achieve the low-cost operation of secondary electric railway lines. The connection between automation level and operating cost is investigated and the importance of other factors, such as simplification of fixed installations and special rolling stock, is also discussed.

The need for performing freight displacements fitting both the just in time manufacturing technique and low environmental impacts led transportation researchers' interest to integrated transport chains. Intermodal networks are composed of nodes and links, and their competitiveness, with respect to the road transport, depends on the performances of each network component, and on the whole network organization. This work deals with integrated transportation terminals (i.e., the network nodes), and it presents an interport model, the guidelines of a model-based simulation tool, and a cost function which was purposely drawn to evaluate the terminal performances.

The study and design of non-industrial vehicles, which may be used in environments dangerous for human beings, is gaining considerable interest. For this purpose, hybrid remote controlled vehicles are those giving a wider range of uses. Issues to be tackled include the mechanical handling problems, artificial vision of the vehicle, remote control and data transmission, power supplies and controls. All these subsystems, though different, are often interacting among them; hence the subsystem study is to consider this fact. The European EUREKA Project to design and build the AMR1 (advanced mobile robots) to be used in unfavourable environments in the case of emergency operations is presented. Particular attention is focused on the electrical system and its control. >

A quasi-zero reactive power demand which is mandatory in single-phase AC (25 kV/50 Hz) traction systems is considered. Multilevel converter structures and high-performance control techniques have been developed to fulfil this goal in AC heavy traction drives. The tasks of the three level rectifier are described in detail. The current control logic is particularly suitable for applications to multilevel bridges. Advantages deriving from the use of a medium-voltage converter with three different DC potentials are discussed. Digital simulation performed using the general-purpose electromagnetic transients program made it possible to verify the effectiveness of the regulating techniques on the whole system. By controlling converters suitably, the reactive power flowing was reduced to quasi-zero values having a constant voltage on the DC-link and minimizing the harmonic content of the line current in every load condition. Another regulation technique was studied to balance the voltage on condensers which, acting exclusively on the rectifier and not using dissipating techniques or raising the device switching frequency, manage to keep the unbalance DV within a prefixed band. >

In the last ten years, an efficient Security Management System (SEMS) has acquired an important role for organizations working in transportation sector. In many cases, Critical Infrastructure legislation plans specific and mandatory quality requirements for the implementation of a security management system. The organizations are encouraged by the legislative requirements and the competitiveness to certify the SEMS in accordance with the current international standards (e.g. ISO 27001 and ISO 28000). As well known, certification can be either a mandatory or a voluntary process but it is usually voluntary and qualitative. In the SEMS, as in other management systems, current certification uses a qualitative approach deriving from the ISO 9000. Normally in certification, quantitative assessment characterizes only some technological systems while every other application including human factor or procedures uses qualitative assessment. The development of security management system certification should bring to introducing risk-based and quantitative assessment methods. Benefits arising from the residual risk quantification of the SEMS can set certification a tool enabling to bargain with insurances, a warranty for the investments undertaken when facing stakeholders and shareholders, a proof to justify decisions during a legal action and last but not least a good publicity for company's image and hence company's competitiveness. This paper proposes the implementation of risk-based methodologies in use by process engineering to achieve a quantitative assessment of security management systems. The methodology is exposed and applied to a railway case study. The first steps show how to analyze the system (study of macro operability functions, identification of subsystems, etc.) and how to integrate technological, human and procedural aspects by flow charts. The later steps describe how to manage threats, vulnerability and criticality of Critical Infrastructure subsystems and how to identify “primary causes” and “Top Event consequences” drawing fault trees and event trees, and finally how to calculate the residual risk for security management system. In conclusion, the methodology is applied on a case study of one railway subsystem and the results of the quantitative risk analysis are exposed.

This paper describes a program for the solution of boundary-value problems of the elliptic type by means of the finite-element method and a generalized finite-difference method developed by the authors. The program is oriented toward the reduction of input operations to those strictly needed to define a given problem physically, and it has been designed to allow automatic grid optimization. The generalized finite-difference method can handle completely irregular grids, and allows the discretization of any form of second-order elliptic equation under general boundary and interface conditions. To show the potentiality of the method, an example of magnetic field problem with sharp boundary, non-homogeneous anisotropic material and non-uniform current density distribution is presented, and the results are compared with the theoretical solution. Finally, the results obtained and the potentiality of the program are discussed.

A new class of reluctance machines has been developed and tested at the Electrical Engineering Dept. of the University of Genoa. The machine structure consists of a stator similar to that of an induction machine with two three-phase windings, 2p and 4p poles respectively (p integer), and of a rotor with p poles and no winding. The machine behaves like a typical reluctance machine. The two stator windings can be supplied with variable frequencies, giving the possibility of a continuous speed regulation. A remarkable performance is that, for pl and frequency 50 Hz for both windings, the ihachine has a 6000 rpm synchronous speed, as a "single pole" machine. The complete theory of the machine. is ptesented in the paper, and the experimental results obtained on some prototypes are displayed and discussed.

Several railway networks and all metro-rail systems are fed by electrical substations (ESSs) equipped with diode AC/DC converters which frequently do not lead to satisfactory performance due to line voltage drop and load sharing among substations. Starting from the formulation of a general model of electric traction systems, the authors deal with the benefits of substation voltage regulation. Some regulation strategies, based on minimization of objective functions, have been tested through computer simulation whose results show that effective regulating actions can be achieved by assuming a cost function that takes into account both the line voltage and power delivered by electrical substations.

The ability to analyse layers within a paint sample is important both for historical studies as well as determining the most suitable method for restoration. The difficulty in physically separating these very thin layers makes detailed analysis difficult, and a combination of destructive and non-destructive techniques are needed. Laser pyrolysis/gas chromatography - mass spectrometry (LaPy/GC–MS) is a technique that has proved successful in the analysis of geological samples which pose the same difficulties for analysis, but it has not yet been tried on paint cross sections. This study presents preliminary results of applying LaPy/GC–MS on standard mock-ups for identification of organic compounds used as varnishes, binders and colourants. The technique was shown to be particularly effective for the identification and localisation of natural resins and synthetic colourants. Moreover, the integration between this technique and other stratigraphical analyses may allow the complete characterisation of the composition of organic substances in paint cross-sections.

The analysis of dyes in cultural heritage samples is a well-known challenging task, due to their inherent high tinting strength and consequent low concentration in the carrying matrix a fact that severely limits the number of analytical techniques that can be efficiently and micro-destructively employed for their detection and unambiguous identification. In the present study, an advanced and alternative SEIRA based analytical protocol for the analysis of small quantities of synthetic colorants has been proposed. The method has been set up for the identification of Acid Orange 7 (AO7) using Au nanoparticles obtained by laser ablation in solution (LASiS). Analyses have been performed applying a drop containing a mixture between the colorant and the Au colloidal solution in its unaggregated state on a gold coated glass slide for RAS (Reflection Absorption Spectroscopy) analysis. The first results showed that, thanks to the enhancement produced by the nanoparticles, it is possible to analyze small amount of diluted solutions containing the colorant. Thus, the method has been successfully applied for the analysis of few pieces of dyed wool, after the development of a suitable micro extraction procedure.

The present research was aimed at exploiting and evaluating the potentialities of FT-NIR microscopy, as a complementary approach to analysis in the MIR region, for the chemical characterisation of paint cross sections. Even if FT-NIR technique is still underutilised in the field of cultural heritage investigations, the integrated use of information recorded in the NIR and in the MIR regions proved to be extremely useful in the molecular investigation of organic and inorganic substances. In fact, combination and overtone bands present in the NIR region, even if weaker and less selective than those in the MIR region, are not distorted by reflection phenomena. Furthermore, NIR spectra can be efficiently used as a spectral fingerprint for the stratigraphic characterisation of paint cross sections. The proposed analytical protocol was applied on two historical samples, presenting different stratigraphic structures. Suitable chemometric methods were applied for the elaboration of multivariate chemical maps recorded in the range 700–7500 cm − 1 . In particular, a comprehensive and efficient procedure based on an interactive brushing approach, which combines the structural information of the score scatter plots with the spatial information of the PC score maps, was used. Interestingly, NIR data allowed a thorough characterisation of paint structures, providing information for the identification of components and suggesting the differentiation among different types of proteins. Moreover, NIR spectra permitted to achieve an efficient distinction of different classes of natural resins, demonstrating that, even working at a microscopic level, the NIR region may support the identification of different terpenoid materials. Multivariate analysis performed on MIR data did not provide satisfactory results, probably due to the distortion of the spectra and overlapping of bands. Nevertheless, MIR outcomes were investigated to support the interpretation of NIR spectra and in attempt to define an integrated protocol for the characterisation of complex paint mixtures.

The present research is aimed at introducing a suitable approach for the exploitation of the hyperspectral data obtained by μATR-FTIR analyses of paint cross-sections. The application of principal component analysis for chemical mapping is well-established, even if a very limited number of applications to μFTIR data have been reported so far in the field of analytical chemistry for cultural heritage. Moreover, in many cases, chemometric tools are under-utilized and the outcomes under-interpreted. As a consequence, results and conclusions may be considerably compromised. In an attempt to overcome such drawbacks, the present work is proposing a comprehensive and efficient procedure based on an interactive brushing approach, which combines the structural information of the score scatter plots and the spatial information of the principal component (PC) score maps. In particular, the study demonstrates not only how the multivariate approach may provide more information than the univariate one, but also how the integration of different chemometric tools may allow a more comprehensive interpretation of the results with respect to the studies up to now reported in the literature. The examination of the average spectral profile of each score cluster, jointly with the loading analysis, is functional to characterize each area investigated on the basis of its spectral features. A multivariate comparison with spectra of standard compounds, projected in the PC score space, helps in supporting the chemical identification. The approach was validated on two real case studies.

The characterization of the organic components in a complex, multilayered paint structure is fundamental for studying painting techniques and for authentication and restoration purposes. Proteinaceous materials, such as animal glue, are of particular importance since they are widely used as binders, adhesives and for gilding. Even though proteins are usually detected by chromatographic and proteomic techniques, immunological methods represent an alternative powerful approach to protein analysis thanks to the high specificity of antigen–antibody reactions. Our previous studies demonstrated that ovalbumin and casein could be localized in paint cross-sections with high sensitivity and good spatial resolution (i.e. within the single painting layers) by using chemiluminescent (CL) immunochemical microscope imaging. In the present research work, we describe for the first time the immunolocalization of collagen (the main protein of animal glue) in paint cross-sections by CL imaging microscopy. Two different analytical protocols have been developed, allowing either the detection of collagen or the simultaneous detection of collagen and ovalbumin in the same paint sample. The assays were used to detect collagen and ovalbumin in cross-sections from model samples and historical paintings (a wall painting dated to 1773–1774 and a painted wood panel of the Renaissance period) in order to achieve information on paint techniques and past restoration interventions.

The present contribution is based on the work carried out within the work package focused on the identification and analysis of existing directives for risk assessment and evaluation. The final aim is to establish indicators to be included into the final model of a European Cultural Heritage Identity Card (EU-CHIC).It has emerged how, currently, there are several regional or national projects aiming at registering, monitoring and preserving the immovable Cultural Heritage. The most complete risk assessment methodologies have been developed in those countries where the risks are highly relevant and seriously endangers built heritage. These results however reflect single country situations, while it seems that there is a need to develop guidelines to be globally accepted and shared within a larger European perspective. In Europe, several projects and tools are already available to the identification of natural hazards. It is worth mentioning the availability of maps addressing specific risks and hazards and their graphical distribution, which were developed by the European Spatial Planning Observation Network (ESPON). The results achieved by ESPON might be considered in conjunction with those obtained by research projects (Noah’s Arc, Climate for Culture, PERPETUATE, FIRESENSE, etc..) to provide a better understanding of the impact of climate change on cultural heritage and to determine risk priorities at a country and regional level. As far as risk assessment methodologies are considered, local and national projects have developed best practices which are discussed in details.

Le numerose ricerche scientifiche mirate allo studio della caratterizzazione chimica ed alla determinazione dello stato di conservazione di inchiostri presenti in antichi manoscritti sottolineano il ruolo fondamentale giocato dalle indagini diagnostiche e dall’analisi chimica in questo particolare ambito di ricerca. Per quanto attiene l’Evangeliario, è stato adottato uno specifico protocollo di indagine scientifica integrato che si è avvalso di due complementarimetodologie di analisi di tipo non invasivo quali l’imaging multispettrale e la fluorescenza a raggi X portatile. L’applicazione di un tale protocollo diagnostico non invasivo, infatti, è ampiamente utilizzata nell’ambito della scienza della conservazione dei beni culturali, ricoprendo un ruolo di primaria importanza, in particolare nello studio di manufatti policromi.

The study deals with some of the material aspects that can help interpret the results that have already been obtained with non-invasive analytical techniques (Part I). In particular, a deeper understanding of the painting technique adopted in The Communion of the Apostles has been achieved and used to verify the presence of typical features ascribable to the Flemish painting tradition. In fact, the presence in all the Uomini Illustri (Famous Men) portraits of typical features of fifteenth-century Flemish paintings, among which is the stratigraphic location, in direct contact with the gypsum ground, of the underdrawing material and the detection of a primuersel layer, has been confirmed. At the same time these features are not uniformly present in all of the 28 portraits and not even within each single portrait, where more local features of painting technique have been observed, such as the use of an imprimitura typical of Italian fifteenth-century paintings. All the analytical results seem, therefore, to confirm that the paintings have been executed by an artist well acquainted with Flemish painting materials and technique but, at the same time, both the underdrawings and some characteristics typical of the Italian painting tradition appear to suggest the contribution of local artists.

The 28 portraits of the Uomini Illustri (Famous Men) were ordered by Federico da Montefeltro to decorate his studiolo in Urbino c.1473–1476. Initially the Famous Men were painted on seven panels, with four portraits on each. They are now separated into two groups, 14 in the Musée du Louvre, Paris and 14 in the Ducal Palace of Urbino. No testimony on the context of the creation itself was left and art historians have claimed that the paintings were created by a Flemish painter, Justus of Ghent and finished by a Spanish painter, Pedro Berruguete. This hypothesis has now been reconsidered. A reconstruction of the Urbino studiolo decoration was given by Pasquale Rotondi in 1973, based particularly on iconographical considerations and on a partial material study. New analyses were performed at the Centre de recherche et de restauration des musées de France (C2RMF) in 2008, enabling the various modifications that the portraits have undergone over the centuries to be brought to light. The results of the Italo-French collaboration presented in this paper allow hypotheses on the original decoration of the studiolo to be proposed.

This paper describes how the new generation of supervision systems in the railway industry can achieve operation from display process variables to all automated control where the human just monitors the automaton. In the railway specific industry, supervision is organized in switching zones and aims to be centralized in an Integrated Control Center. These centers implement integrated and computer based systems that perform train protection, train operation and supervision. Thus railway dispatchers using supervision have their tasks considerably simplified. Although considered today as not safety critical, railway supervision systems can contribute to safety in some scenarios where an appropriate decision of a supervision operator could notably reduce the severity of accidents. That is in particular the case for residual scenarios (intervention of maintenance teams on the tracks, manual operation of trains not protected by train protection system, coupling/uncoupling, emergency requiring the stopping and evacuation of a train etc) only covered by procedure, thus requiring human intervention by a person supposed correctly informed on the state of the system, thanks to the data provided by the supervision system.

Among non destructive techniques for the determination of the chemical composition of glasses X-Ray Fluorescence portable spectrometry avoid any sample manipulation and has the great advantage of in situ measurements. In addition, in order to verify the heterogeneous chemical composition and to identify different sampling points, such technique allows an extensive investigation of the single tesserae and of wider areas of the mosaics. To compare performances and limits of destructive and non destructive techniques, ICP-AES analysis and portable X-Ray Fluorescence spectrometry have been performed on glass standards and on a selection of mosaic tesserae. This is a laboratory test to be developed into an in situ analytical protocol at use and advantage of art historians and conservators for their “first-sight” knowledge of the mosaic glass characteristics.

In this study the two paintings the Holy Family of Christ and St John Baptist (176 x 75 cm) and the Baptism of Christ located in the Saint Andrea church, Mantua have been studied to achieve information on the painting technique. Indeed, the attribution of the paintings to Mantegna has been the subject of many controversial discussions among scholars. Therefore, with the purpose of making available to scholars further useful information concerning the painting technique adopted and the paint materials constitution, a complement of scientific examinations, carried out in situ with the use of non-invasive portable analytical techniques, such as digital multi spectral scanner imaging system and energy dispersive X-Ray Fluorescence (EDXRF) have been performed. It has been hence possible to evaluate the state of conservation, study applied artistic technique, distinguish and locate past restoration interventions and analyze colour and pigments. This has been particularly done by complementing the chemical information gathered through the use of EDXRF with the false-colour IR technique: a computer-based technique which combines colour images and reflectograms to create a “pseudo-colour” image where each pigment is represented by a specific false-colour that depends on its type of interaction with the infrared light.

The characterization and localization of proteins and other organic components in the complex stratigraphy of paintings is crucial for authentication and studies of painting techniques. With this aim we have developed a new ultrasensitive immunochemical procedure for the detection of the protein ovalbumin (chicken egg white albumin), present in binding media or varnishes, in painting cross-sections. The technique is based on chemiluminescence imaging detection combined with optical microscopy, and allowed the sensitive localization of the target protein in cross-sections with high spatial resolution. In order to evaluate its performance, the method was first applied to standard samples (also containing different common pigments), then used for the localization of ovalbumin in samples obtained from a Renaissance wood painting.

False-color infrared represents a well known method for non-invasive pigment identification in artworks. This is particularly useful in the field of conservation of cultural heritage as it provides useful information about painting materials, techniques, retouches. However, the interpretation of a false-color image is still carried out just by “naked eye” evaluation, thus suffering from the doubts of a subjective exam. To this aim, we designed a computer-assisted system to support pigment identification in an artwork. Our system includes automated procedures for selecting investigation areas and for matching unknown pigments on the considered artwork with known standards in a database. Finally, information is made available for discussion among remotely located investigators through a shared virtual environment (i.e., a groupware).

Computational Mechanics Inc. USA