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This paper proposes a novel method to reliably calibrate a pair of sensorized insoles utilizing an array of capacitive tactile pixels (taxels). A new calibration setup is introduced that is scalable and suitable for multiple kinds of wearable sensors and a procedure for the simultaneous calibration of each of the sensors in the insoles is presented. The calibration relies on a two-step optimization algorithm that, firstly, enables determination of a relevant set of mathematical models based on the instantaneous measurement of the taxels alone, and, then, expands these models to include the relevant portion of the time history of the system. By comparing the resulting models with our previous work on the same hardware, we demonstrate the effectiveness of the novel method both in terms of increased ability to cope with the non-linear characteristics of the sensors and increased pressure ranges achieved during the experiments performed.

In this study, a textile-based wearable strain sensor is fabricated to monitor human muscular activities with high sensitivity and large working range. To achieve electrical conductivity, a gum-like sticky polyvinyl acetate-co-vinyl laurate polymer (commercial name: VINNAPASS) is mixed with 50 wt % of carbon nanofiber (CNFs) using ethyl acetate as co-solvent. The VINNAPASS/CNFs-based ink is spray coated onto a stretchable polyethylene terephthalate fabric (commercial name: Lycra) and subsequently covered and stabilized with polydimethylsiloxane protective layer. Another reference sensor is also prepared using thermoplastic polyurethane (TPU) with equal concentration of CNFs. The strain sensor made with VINNAPASS demonstrated sheet resistance, maximum elongation at break, gauge factor (GF) and working range of 32.27 ± 1.60 Ω/□, 230 ± 6%, 67.12, >170% as compared to 48.44 ± 2.33 Ω/□, 122 ± 7%, 39.97 and ~100% for the sensor made with TPU, respectively. Moreover, the VINAPASS-based strain sensor displayed complete self-healing and >90% reversible electrical properties on damage, while the TPU-based sensor was not healable. Finally, the VINNAPASS-based sensor is used to monitor folding-unfolding of human finger and wrist as well as bicep muscle contraction and relaxation, and is envisioned for monitoring human muscular motions during physical activities and exercising.

We present the first results obtained with a prototype of the PET read-out electronics of the trimodal PET/MRI/EEG TRIMAGE scanner. The read-out is based on the 64-channel TRIROC ASIC and on an acquisition board that will control up to 12 ASICs. The output of each ASIC is processed in parallel and sent to a host system that in the final version will receive data from 18 acquisition boards. Blocks of 64 SiPMs are one-to-one coupled to a dual-layer staggered LYSO crystal matrix and read by a single ASIC. The FPGA reads the sparse output from the ASICs and reconstructs for each event a full image of the light pattern coming from the LYSO matrix. This pattern can be then processed on-line or sent to the host PC for post-processing. Early tests were conducted by using a prototype board with single LYSO crystals of ${3.3} \textrm {mm}\times {3.3} \textrm {mm} \times {8} \textrm {mm}$ and dual layer staggered LYSO matrices. Results show that the ASIC can sustain input rates above 58 kHz on all its channels, with small variations depending on the discriminating thresholds, being this limit due its digital output stage. With the single crystals setup, we obtained an energy resolution of 10.7% at 511 keV and a coincidence time resolution of 420 ps FWHM. With the staggered matrix the obtained mean energy resolution was 16% on the top layer and 18% on the bottom layer. The flood maps obtained with the LYSO matrix setup show that the pixels on both the staggered levels are clearly identifiable.

The importance of searching signals from “non-standard” physics has been growing in the last years, in spite of the astounding success of the Standard Model in predicting particle existence and behaviour. In particular the Lepton Flavor Violating (LFV) processes, and exspecially the µ → e + γ decay, are a very promising field to probe effect of physics beyond the Standard Model [1]. Thus the MEG experiment has been proposed and is in an advanced phase of construction at the Paul Scherrer Institute (PSI).

The MEG experiment started taking data in 2009 looking for the Standard Model suppressed decay μ → e + γ, which, if observed, can reveal Beyond Standard Model physics. It makes use of state-of-the art detectors optimized for operating in conditions of very high intensity, rejecting as much background as possible. The data taking ended August 2013 and an upgrade R&D is started to push the experimental sensitivity. The present upper limit on the decay Branching Ratio (BR) is presented, obtained with the subset of data from 2009 to 2011 run, together with a description of the key features of the upgraded detector.