A Web-Based Distributed Virtual Educational Laboratory

Evolution and cost of measurement equipment, continuous training, and distance learning make it difficult to provide a complete set of updated workbenches to every student. For a preliminary familiarization and experimentation with instrumentation and measurement procedures, the use of virtual equipment is often considered more than sufficient from the didactic point of view, while the hands-on approach with real instrumentation and measurement systems still remains necessary to complete and refine the student's practical expertise. Creation and distribution of workbenches in networked computer laboratories therefore becomes attractive and convenient. This paper describes specification and design of a geographically distributed system based on commercially standard components

Channel Selection for Optimal EEG Measurement in Motor Imagery-Based Brain-Computer Interfaces

A method for selecting electroencephalographic (EEG) signals in motor imagery-based brain-computer interfaces (MI-BCI) is proposed for enhancing the online interoperability and portability of BCI systems, as well as user comfort. The attempt is also to reduce variability and noise of MI-BCI, which could be affected by a large number of EEG channels. The relation between selected channels and MI-BCI performance is therefore analyzed. The proposed method is able to select acquisition channels common to all subjects, while achieving a performance compatible with the use of all the channels. Results are reported with reference to a standard benchmark dataset, the BCI competition IV dataset 2a. They prove that a performance compatible with the best state-of-the-art approaches can be achieved, while adopting a significantly smaller number of channels, both in two and in four tasks classification. In particular, classification accuracy is about 77-83% in binary classification with down to 6 EEG channels, and above 60% for the four-classes case when 10 channels are employed. This gives a contribution in optimizing the EEG measurement while developing non-invasive and wearable MI-based brain-computer interfaces

Sodium lactate solutions characterization using Electrochemical Impedance Spectroscopy

Lactate is an important metabolite in human body and, among possible medical applications, it can be used to monitor physical activity. Actually, its concentration represents a clear indication whether optimal training intensity is kept or if muscles are under anaerobic conditions. Routine procedures to measure lactate concentration during physical activity are represented by invasive measurements, which require blood sampling from the patient or the athlete. So, a great advantage would be derived by the possibility to monitor this analyte using non-invasive techniques. Considering the possibility to measure lactate in human sweat during sport activities, this paper presents the characterization of saline aqueous solutions containing sodium lactate by means of Electrochemical Impedance Spectroscopy (EIS). Measurements were performed using a two-electrode electrochemical cell and acquired spectra were analyzed also by means of equivalent electrical circuit (EEC) modeling. Results show an effect due to lactate concentration on solution impedance in the high-frequency region of spectrum, where a change in solution resistance is measured. At the same time, no changes in the measured capacitance were found. Future work will study the electrochemical behavior of lactate solutions also at higher frequencies to further investigate the possible use of EIS for lactate levels monitoring during sport activities

A low-cost automatic acquisition system for photogrammetry

Photogrammetry is a non-destructive technique commonly employed in the cultural heritage field for reconstructing a 3D virtual replica of an artifact by simply taking several photos of the artifact itself from different points of view. The 3D model can be used either for documenting the artifact or for preserving its geometrical information and appearance. Moreover, by using a digital 3D model is extremely easy sharing information with the public and researchers without physically moving the artifact, and this represents a unique opportunity which cannot be achieved with traditional methods. Unfortunately most systems already present on the market are complex and costly both due to their hardware and software. This paper presents a novel acquisition system which is extremely cheap and can be easily arranged in any conservation laboratory. The solution is based on a simple acquisition system designed with the aim of providing researchers with a user-friendly and low-cost platform for the reconstruction of an artifact 3D model. The proposed system can be virtually interfaced to every commercial camera and can be integrated with several 3D reconstruction software. As an example, the authors employed a free open-source software referred to as Meshroom

Environmental monitoring solution for cultural heritage

Environmental monitoring is crucial factor in the safeguard and conservation of the cultural heritage. Unsuitable environmental conditions can easily accelerate the degradation of several materials and, as consequence, damage the stored artifacts. Moreover, environmental conditions can easily change in an unpredictable way and, therefore, the employment of an environmental monitoring system is mandatory in almost all locations, including museums, storage rooms and outdoor exhibitions. This paper tries to explain the main constraints required for environmental monitoring in the cultural heritage field. Moreover, a novel distributed monitoring system, developed at Politecnico di Torino, is described and compared to several solutions that are commercially available. The proposed solution demonstrated excellent characteristics which satisfy the requirements of environmental monitoring in the cultural heritage at a very competitive cost

Mixed Neural-Conventional Processing to Differentiate Airway Diseases by Means of Functional Noninvasive Tests

This paper describes a processing technique that can be used to combine information from different medical analyze to discriminate between different pathologies that have similar symptoms. The paper is focused on the differentiation between asthma, bronchitis, and emphysema, using only functional noninvasives tests, but the proposed technique can be easily applied to other similar situations where different tests have to be used to identify a pathology. The technique is based on mixed neural-and-conventional processing that not only suggests the pathology, but also estimates the reliability of this suggestion

A Client-Server Architecture for Distributed Measurement Systems

This paper describes a client-server architecture for the remote control of instrumentation over the Internet network. The proposed solution allows multiuser, multi-instrument sessions by means of a queueing and instrument locking capability. Client applications can be easily developed by using conventional high-level programming languages or well-assessed virtual instrumentation frameworks. Performance tests are reported; they show the low overhead due to network operation with respect to the direct control of instrumentatio

Corrosion prediction of metallic cultural heritage assets by EIS

Electrochemical Impedance Spectroscopy (EIS) was used to predict corrosion behaviour of metallic Cultural Heritage assets in two monitoring campaigns: 1) an iron bar chain exposed indoor from over 500 years in the Notre Dame Cathedral in Amiens (France); and 2) a large weathering steel sculpture exposed outdoor from tens of years in Ferrara (Italy). The EIS portable instrument employed was battery operated. In situ EIS measurements on the iron chain could be used to investigate the phenomena involved in the electrochemical interfaces among various corrosion products and assess and predict their corrosion behaviour in different areas of the Cathedral. Meanwhile, the sculpture of weathering steel, like most outdoor artefacts, showed rust layers of different chemical composition and colour depending on the orientation of metal plates. The EIS monitoring campaign was carried out on different areas of the artefact surface, allowing assessment of their protective effectiveness. Results of EIS measurements evidenced how employing a simple test that could be performed in situ without damaging the artefacts surface is possible to quickly gain knowledge of the conservation state of an artefact and highlight potential danger conditions

Atmospheric corrosion of outdoor bronze artefacts: The case study of 'Katarsis', by Magdalena Abakanowicz

The conservation of cultural heritage metallic items is deeply connected to the investigation of the corrosion phenomena affecting the metallic surface and to the study of the influence of the surrounding environmental parameters. This paper describes the case study regarding the metallic artwork 'Katarsis' of the Gori Art Collection at Fattoria di Celle (Pistoia, Italy), created by the artist Magdalena Abakanowicz. An in-situ multi-analytical approach was employed in order to assess the conservation state of the statues and to ensure their long-lasting preservation. In particular, X-rays fluorescence (XRF), Raman spectroscopy (RS), and X-Rays diffraction (XRD) were used for the identification of the corrosion products, mainly sulphates, and to identify the employed alloy. In this paper, the preliminary results will be presented and discussed

Electrochemical characterization of innovative hybrid coatings for metallic artefacts

In this paper, an electrochemical characterization of two different hybrid coatings is presented, with the specific aim of studying their corrosion protection behavior and better understanding their possible application in the cultural heritage field. The two formulations under study were epoxy resin containing silica nanoparticles and epoxy resin containing graphene oxide. Electrochemical Impedance Spectroscopy (EIS) and Scanning ElectroChemical Microscopy (SECM) were used to compare the electrochemical behavior of the two coatings and highlight their failure mechanism when immersed in an electrolytic solution containing chlorides. The investigation highlighted the good corrosion protective properties of both coatings; and moreover, thanks to the joined use of the two described analytical techniques, the different water uptake of the two solutions was studied, together with the different evolution of the coating surface morphology when immersed in the electrolytic solution