Search results for "ACOUSTIC"
showing 10 items of 1590 documents
Supplementary material 2 from: Heller K-G, Hemp C, Massa B, Kociński M, Warchałowska-Śliwa E (2018) Paraplangia sinespeculo, a new genus and species …
2019
Supplementary material 2 from: Heller K-G, Hemp C, Massa B, Kociński M, Warchałowska-Śliwa E (2018) Paraplangia sinespeculo, a new genus and species of bush-cricket, with notes on its biology and a key to the genera of Phaneropterinae (Orthoptera: Tettigonioidea) from Madagascar. Journal of Orthoptera Research 27(2): 143-153. https://doi.org/10.3897/jor.27.24243
Optical sensor for remote estimation of alcohol concentration in blood stream
2013
Abstract The purpose of this manuscript is to validate our recently developed novel optical approach for extraction of remote vibration sources as a successful technique to estimate the alcohol concentration in blood stream. This technique is based on the tracking of temporal changes of reflected secondary speckle patterns produced in human skin when being illuminated by a laser beam. Since the skin’s vibrations profile is changed due to the alcohol in the blood stream, the extraction of the vibration profile can be translated into the corresponding alcohol concentration values by means of defining several parameters acting as indicators for the presence of alcohol in the blood stream. We h…
On the harvest of rainfall energy by means of piezoelectric transducer
2013
In this paper a detailed study on the harvest of the energy contained in rainfall by means of piezoelectric transducers is presented. Diverse studies agree on the level of suitable generated voltage on the electrodes of a piezoelectric transducer subjected to rainfall, but a complete characterization on the supplied power is still missing. This work, in order to limit optimistic forecasts, takes into account the behavior of the transducers subjected to real and also artificial rainfall, condition that has shown promising behavior in laboratory. In order to increase the energy harvesting and also define its limits different loads have been taken into account. Only commercial transducers have…
Recognition of Chip Forms by Means of Dynamic Force Spectrum Analysis
1993
In this study the ability to identify chip forms occurrs in the turning of austenitic stainless steel using dynamic force spectrum analysis has been tested. For this purpose the frequency spectra obtained from various metal cutting tests were recorded along with the static cutting forces. A dual channel analysis, based on the Fast Fourier Transform (FFT), was adopted to help identify the continuous/discontinuous (favourable/unfavourable) chip forming boundary. The results showed an acceptable correlation between the types of the frequency spectra and the types of chip forms. Finally, an original classification of the spectra obtained during turning of AISI 304 (DIN 1.4301) stainless steel i…
Ultrasound Velocity in Bone Under Disrupted Blood Supply
2011
Simulation of laser-generated ultrasonic wave propagation in solid media and air with application to NDE
2009
Ultrasonic methods are well known as powerful and reliable tool for defect detection. In the previous decades focus and interest have been directed to non-contact sensors and methods, showing many advantages over contact techniques where inspection depends on contact conditions (pressure, coupling medium, contact area). The non-contact hybrid ultrasonic method described here is of interest for many applications, requiring periodic inspection in service or after manufacturing. Despite the potential impact of laser-generated ultrasound in many areas of industry, robust tools for studying the phenomenon are lacking and thus limit the design and optimization of non-destructive testing and evalu…
Design and Implementation of Acoustic Source Localization on a Low-Cost IoT Edge Platform
2020
The implementation of algorithms for acoustic source localization on edge platforms for the Internet of Things (IoT) is gaining momentum. Applications based on acoustic monitoring can greatly benefit from efficient implementations of such algorithms, enabling novel services for smart homes and buildings or ambient-assisted living. In this context, this brief proposes extreme low-cost sound source localization system composed of two microphones and the low power microcontroller module ESP32. A Direction-Of-Arrival (DOA) algorithm has been implemented taking into account the specific features of this board, showing excellent performance despite the memory constraints imposed by the platform. …
Surgically Assisted Rapid Palatal Expansion An Acoustic Rhinometric, Morphometric and Sonographic Investigation
2001
This study aimed to evaluate the effect of surgically assisted rapid palatal expansion on the skeletal structures of the midface. Ten patients (mean age 28.5 years) were investigated by means of acoustic rhinometry, study model analysis and sonography before and after the procedure of surgically assisted rapid palatal expansion. The measurements revealed that surgically assisted rapid palatal expansion not only resulted in transverse expansion of the maxilla, providing dental arch space for lining up the teeth; the procedure also caused a substantial enlargement of the maxillary apical base and of the palatal vault, providing space for the tongue for correct swallowing and thus preventing r…
Adapting robot paths for automated NDT of complex structures using ultrasonic alignment
2019
Automated inspection systems using industrial robots have been available for several years. The IntACom robot inspection system was developed at TWI Wales and utilizes phased array ultrasonic probes to inspect complex geometries, in particular aerospace composite components. To increase inspection speed and accuracy, off-line path planning is employed to define a series of robotic movements following the surface of a component. To minimize influences of refraction at the component interface and effects of anisotropy, the ultrasonic probe must be kept perpendicular to the surface throughout the inspection. Deviations between the actual component and computer model used for path-planning resu…
Measurement of Pharyngeal Pressure in Patients using Nasal CPAP
1995
In patients with obstructive sleep apnea syndrome (OSAS), nasal continuous positive airway pressure (nCPAP) prevents pharyngeal collapse by applying positive pressure transnasally. Currently there are not objective criteria to determine whether surgical improvement of nasal resistance is necessary in patients undergoing nCPAP treatment. In 16 patients with documented OSAS, inspiratory and expiratory pressures in the pharynx were measured during nCPAP with pressures ranging from 5 to 20 mbar. Identical studies were performed in 12 patients with severe nasal obstruction without OSAS and in eight normal patients. The results of each group were compared to the nasal resistance as measured by a…