1,721,262 research outputs found
Il Saggio G
No full textRelazione degli scavi nel saggio G della villa tardo romana di Palazzo Pignano (CR
Mechanical model of flex sensors used to sense finger movements
No full textFlex sensors change in their electrical resistance value depending on the amount of bend they are subjected.
These sensors can be realized with different techniques, but the mostly adopted are based on a
resistive element film, which can be made of a PEDOT:PSS polymer or of a carbon-based element, printed
on a plastic substrate.
We investigated from a theoretical point of view the mechanical aspect of these sensors related to their
utilization to sense finger movements, to determine the relationship with the electrical behavior. This
was to provide enhanced degrees of understanding and predictability in performances.
Experiments were conducted on custom-made flex sensors based on PEDOT:PSS polymer, to measure
the resistance variations vs. the amount of bend radius induced in the sensors, in either of two opposing
directions (outward and inward).
Results demonstrated that the mechanical behavior influences the electrical counterpart but linearly,
the more the bent the more the increase in the resistance, in a direct proportion. When a nonlinear
behavior is measured, as in the case of commercially available Flexpoint sensors, it was found to depend
only to causes strictly related to physical changes in the resistive element (cracks under stress)
Electrical resistance profiling of bend sensors adopted to measure spatial arrangement of the human body
No full textElectrical Resistance Profiling of Bend Sensors adopted to Measure Spatial Arrangment of the Human Body
Full text linkWe report some techniques we adopted to electrically characterize some commercially available bend sensors, in terms of their resistance variations when curved or angular shaped. This study has the aim of a correct exploitation of the bend sensors in order to adopt them for proper measures of the static postures and kinematics of the total human body, in regards for both the trunk and the limb
reative ion etching characterization of a-siC in cf4-o2 plasma
No full textIn this paper a reactive ion etching process on amorphous silicon carbide (a-SiC) films is characterized by varying the carbon content from 0.73 molar fraction of C (Xc = 0.73) to Xc = 0 (pure a-Si). The film composition was analyzed by electron microprobe analysis. The effect of hydrogen presence in the deposition chamber and of the material doping on the etch rate was considered. The etch rate in a CF4 O2 plasma was investigated as a function of the r.f. power and gas pressure in the etching chamber, taking the loading effect also into account. An appreciable induction time was observed only for pure a-Si. The etch rate, increased in carbon-films, was found to be almost linearly related to the optical energy gap of the material. However, the etch rate was not a consistent function of Xc. An analytical relation between etching rate and r.f. power is proposed. Varying the gas pressure, and a-SiC etch rate slowly rises, remains nearly constant at a maximum value in the range 30-60 mTor, after which it decreases. However, no decrease at higher pressure was seen for the a-Si: H films
Worldwide Healthy Adult Voice Baseline Parameters: A Comprehensive Review
No full textThe voice results in acoustic signals analyzed and synthetized at first for telecommunication matters, and more recently investigated for medical purposes. In particular, voice signal characteristics can evidence individual health conditions useful for screening, diagnostic and remote monitoring aims. Within this frame, the knowledge of baseline features of healthy voice is mandatory, in order to balance a comparison with their unhealthy counterpart. However, the baseline features of the human voice depend on gender, age-range and ethnicity and, as far as we know, no work reports as those features spread worldwide. This paper intends to cover this lack. Our database research yielded 179 relevant published studies, retrieved using digital libraries of IEEE Xplore, Scopus, Web of Science, Iop Science, Taylor and Francis Online, and Scitepress. These relevant studies report different features, among which here we consider the most investigated ones, within the most investigated age-range. In particular, the features are the fundamental frequency, the jitter, the shimmer, the harmonic-to-noise ratio, and the cepstral peak prominence, the most investigated age-range is within 20-40 years and, related to the ethnicity, 20 countries are considered
Feasibility of teleoperations with multi-fingered robotic hand for safe extravehicular manipulations
No full textExtra-Vehicular Activity (EVA) plays such a key role that more and more time is devoted to it in space missions. Nevertheless, EVA presents so many intrinsic critical aspects to result highly hazardous for the human operators. This is why a convenient alternative can be offered by telerobotic manipulations, with multi-fingered robotic hands working in teleoperated mode, to safely and remotely replicate the capabilities of the operator's hands. But at present, remotely controlled robotic hands cannot provide the same dexterity of humans, so this work is intended to experimentally evaluate their feasibility and technological limits when operator's hand gestures are one-to-one mapped directly to a robotic hand device. In particular we demonstrated how state-of-the art sensory gloves, used to measure angles of human finger's joints, can introduce averaged errors of 4.6 degrees in angles, and that these errors increase to 6.5 degrees when remotely replicated by standard anthropomorphic robotic hands
- …
