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This paper describes a system for the measurement of the apparent mass (AM) matrix of standing subjects. The system uses two electrodynamic shakers to generate vibrations along two mutually perpendicular axes (vertical and horizontal) and allows the identification of the full AM matrix with two tests, in which the standing subject is exposed to vertical excitation combined in turn with fore-and-aft and lateral vibration. A 3-D force platform measures the forces and the torques transmitted from the vibrating platform to the feet. The force platform, set up with piezoelectric load cells, has been designed in order to obtain a measurement bandwidth of 20 Hz. The supports of different load cells are meant to minimize bending moments on the sensors and to minimize the axes crosstalk. The force platform has been calibrated with a least-squares approach, using reference masses and a dynamometric hammer. The AM uncertainty, evaluated through the experiments’ repeatability and reproducibility, is lower than 3.4% along the three axes (confidence level 68%). The measurement bandwidth is 20 Hz (±2%) and the crosstalk between orthogonal axes is lower than 5%, in accordance with the design requirements. [ABSTRACT FROM AUTHOR]

This paper describes a method for the comparison of the cooling capability of over-the-counter devices for skin tags removal. The comparison is performed by measuring the heat flux produced by the gas identified assessing the temperature difference across an element with a known thermal resistance; the temperature reached at the interface between the device and the heat-flux meter is also analyzed, although it is different from that of the skin during the treatment. The measurement accuracy has been experimentally evaluated and, with a confidence interval of 95%, is better than 6% for heat-flux measurements and lower than 0.3 °C for temperature measurements. The instrument allowed comparing the thermal efficiency of 19 dimethyl ether and propane devices of different types (dispenser, spray, and foam). Results are by far more reliable than those obtained with tests performed on subjects, where the intrinsic skin thermal properties variability prevents from assessing differences smaller than 30%. [ABSTRACT FROM PUBLISHER]