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This paper is part of the Proceedings of the 2019 Bicycle and Motorcycle Dynamics Conference: A Symposium on the Dynamics and Control of Single Track Vehicles held in Padova, Italy September 9th through 11th in the year 2019.Artifact ID: 34

This poster is part of the Proceedings of the 2019 Bicycle and Motorcycle Dynamics Conference: A Symposium on the Dynamics and Control of Single Track Vehicles held in Padova, Italy September 9th through 11th in the year 2019.Artifact ID: 23

Simulation tools have been widely used to complement experimentation for suspension design in the automotive industry not only for reducing the development time, but also to allow the optimization of the vehicle performance. Both a test method and a simulation tool are presented for the analysis of Noise-Vibration-Harshness (NVH) performances of road vehicles suspension systems. A single suspension (corner) has been positioned on a rotating drum (2.6 m diameter) installed in the Laboratory for the Safety of Transport of the Politecnico di Milano. The suspension system is excited as the wheel passes over different cleats fixed to the working surface of the drum. The forces and the moments acting at the suspension-chassis joints are measured up to 250 Hz by means of five six-axis load cells. A mathematical representation that can accurately reflect tyre dynamic behaviour while passing over different cleats is fundamental for evaluating the suspension system quality (NVH) and for developing new suspension design and control strategies. Since the phenomenon is highly non-linear, it is rather difficult to predict the actual performance by using a physical model. However universal "black-box" models can be successfully used in the identification and control of non-linear systems. The paper deals with the simulation of the tyre/suspension dynamics by using Recurrent Neural Networks (RNN). RNN are derived from the Multi Layer Feed-forward Neural Networks (MLFNN), by adding feedback connections between output and input layers. The Neural Network (NN) has been trained with the experimental data obtained in the laboratory. The results obtained from the NN demonstrate very good agreement with the experimental results over a wide range of operation conditions. The NN model can be effectively applied as a part of vehicle system model to accurately predict elastic bushings and tyre dynamics behaviour.

The authors describe a rare complication following total gastrectomy or reconstruction using a Roux-en-Y loop: the presence of a metal mandrel used to insert the nasogastric tube in the end tract was discovered during esophagojejunal anastomosis. The object was extracted by esophagoscopy without damage to the patient.

A report is given on the various research activities concerning radioanalytical chemistry performed in the following fields; (a) radiochemistry; (b) non-nuclear methods; (c) instrumental neutron activation analysis; (d) computer analysis of γ-ray spectra. All these activities are carried on in the frame of two surveys extended to the whole Italian territory: the first one on the radioactive environmental contamination both of natural and of artificial origin; the second one on a number of non-radioactive trace elements, with a particular emphasis upon their presence, as contaminants, in the food-chain and upon their uptake by man.

Thermal neutron activation analysis and a large-volume high-resolution Ge(Li) gammaray spectrometer, connected on-line to a DEC PDP 8/L computer, have been used to measure the concentrations of Na, Sc, Cr, Fe, Co, Ni, Zn, As, Se, Br, Rb, Ag, Sb, Cs, W and Hg in some Italian subsurface water samples. The instrumental method requires neither a chemical separation technique nor a pre- or post-concentration of the trace elements to be detected. As a consequence, this method eliminates many inherent errors associated with chemical determinations. The technique is sensitive, precise and particularly suitable for routine analysis of many trace elements at both natural and pollution levels in water samples. The interferences due to fast neutron (n, p) and (n, α) reactions are not appreciable, with the only exception of the54Fe(n, p)54Mn and58Ni(n, p)58Co reactions. Losses of volatile, elements, e. g. As, Br and Hg, during irradiation proved to be negligible.

An apparatus for measuring excess volumes of dissolved gases in liquids at low temperature, for pressures below 100 atm and for concentrations about 1%, is described. The apparatus has been tested measuring the excess volume for A‐N2 and H2‐N2 systems.

On the basis of the several studies recently published on the concentration of Hg and other heavy elements in seafish and especially tunafish a work as been carried out to determine the intake due to canned tunafish for the italian population. Instrumental activation analysis has been applied to tunafish canned samples avaible on the market in Rome. The following trace elements have been measured: Cr, Se, Hg, Cs, Fe, Zn, Co, Sb. The intake of Hg and other elements through the canned tuna foods have been evaluated on the basis of the production of such foods in Italy. The tunafish contribution to the total trace elements intakes has been determined by comparing the trace elements concentrations in the canned tunafish with those referred to diets that are representative for the italian population. The results obtained have demonstrated that the trace elements intake through the diet is not significantly influenced by the tunacanned foods intake.