[en] In the broad and varied field of sensors this conference reviews thermal sensors for temperature measurements, gas sensors for gas analysis (for example analysis of exhaust gases from vehicles), optical fiber sensors, applications for optics, mechanics, robotics and signal processing. In particular one of the applications concerns acoustical transducers operating in liquid sodium for LMFBR reactors

[en] This invention relates to a multiple channel electrode partially implantable in the cochlea for transmitting to the auditory nerve electric signals from an outside electronic device such as an analyzer converting acoustic signals into electric signals

[en] The ultrasonic centring device described features at least one ultrasonic converter located inside a containment this converter emitting an ultrasonic wave, devices to pick up the various ultrasonic echoes coming from the walls of the containment, instruments for measuring the time interval separating the reception of the various echoes and appliances for moving the converter(s) until the various echoes are received at the same time by the echo receiving units

[en] A sufficient amplification reserve can be reached even for free us-waves for many testing problems. Hereby there is a chance to introduce the advantages of the absence of coupling-media into practice. The results in pipe-waves are assured to a for extent in the laboratory stadium for the detection of cross-cut faults and free waves for perpendicular and angular incoupling of transversal waves. (DG)

No abstract available

[en] Propagation of ultrasound through a complex composite sample may exhibit phase interference between two or more sonic-rays if differences in transit time are less than the pulse length. The transit time spectrum of a test sample, equivalent to its impulse response, was derived through active-set deconvolution of ultrasound signals with, and without, the test sample. The aim of this study was to test the hypothesis that in cases where only the transmit ultrasound transducer’s digitally-coded excitation signal is available, hence not the input ultrasound signal without the test sample, incorporation of the transducer impulse response may increase both accuracy and precision of ultrasound transit time spectroscopy. A digital 1 MHz sinusoid signal was used to create an ultrasound pulse that was propagated through a 5 step-wedge acrylic sample immersed in water. Transit time spectra were obtained through deconvolution utilising an ultrasound input signal, along with a digital input signal, with and without incorporation of the transducer impulse response. Incorporation of the transducer impulse response reduced a quantitative measure of noise-to-signal ratio by a factor of 12.

The paper has demonstrated the potential for increased accuracy and precision of transit time spectroscopy when the transducer impulse response is incorporated within active-set deconvolution analysis. (paper)

No abstract available

[en] This work describes an ultrasonic inspection procedure designed for verifying coarse-grained structure materials, which are commonly used on nuclear reactors. In this case, conventional phased array techniques cannot be used due to attenuating characteristics and backscattered noise from microstructures inside the material. Thus, synthetic aperture ultrasonic imaging (SAFT) is used for this approach in contact conditions. In order to increase energy transferred to the medium, synthetic transmit aperture is formed by several elements which generate a diverging wavefront equivalent to a virtual ultrasound source behind the transducer. On the other hand, the phase coherence technique has been applied to reduce more structural noise and improve the image quality. The beamforming process has been implemented over a GPU platform to reduce computing time

[en] For the purpose of domestic production of ultrasonic transducer, experiments on material selection for backing and matching layer, and electrical impedance matching between transducer and equipment were performed. The characteristics of manufactured transducers with experimental results were analyzed and compared with foreign products. Through the evaluation of the transducers manufactured and the comparison with foreign products, it is confirmed that the transducers manufactured show the good performance characteristics and efficiency

[en] Published in summary form only