A vibration measurement sensor (3) adapted to measure the vibrations formed on a test object (O) with moving mechanical systems, at least one noise measurement sensor (4) adapted to measure sound intensity and/or particle velocity and/or sound pressure in at least one direction, i.e. on one axis, and a vibration and noise mapping system (1) that is adapted to control the vibration measurement sensor (3) and the noise measurement sensor (4), to provide the vibration and acoustic performance data of the test object (O) according to the data obtained from these units (3, 4) and to identify the areas on the test object (O) that are problematic or need to be studied further in order to improve vibration and acoustic performances thereof, and to control the operation of test objects (O) such as moving mechanical systems under different conditions.

A measuring device and measuring system which accurately measure a pulse wave propagation velocity. The measuring instrument includes: a fixing part attachable to and detachable from a subject; a first piezoelectric sensor fixed to the fixing part; a second piezoelectric sensor fixed to the fixing part at a prescribed distance from the first piezoelectric sensor; and an analyzing part for calculating a pulse wave propagation velocity in the subject according to time difference between time of detection of peak voltage by the first piezoelectric sensor and time of detection of peak voltage by the second piezoelectric sensor, and the prescribed distance.

A measuring device and measuring system which accurately measure a pulse wave propagation velocity. The measuring instrument includes: a fixing part attachable to and detachable from a subject; a first piezoelectric sensor fixed to the fixing part; a second piezoelectric sensor fixed to the fixing part at a prescribed distance from the first piezoelectric sensor; and an analyzing part for calculating a pulse wave propagation velocity in the subject according to time difference between time of detection of peak voltage by the first piezoelectric sensor and time of detection of peak voltage by the second piezoelectric sensor, and the prescribed distance.

Apparatus (10) and methods for measurement of pore pressure in rock formations through a metal borehole casing (32) after a well is cased and cemented, are described. Such measurements may be accomplished by using the Dynamic Acoustic Elasticity (DAE) method for characterizing nonlinear parameters by perturbing a selected rock formation region with a High Amplitude, Low Frequency (HALF) acoustic strain wave, and probing this region using a Low Amplitude, High Frequency (LAHF) acoustic wave (18), (22). Time reversal techniques (36) may be employed for focusing acoustic energy into the formation in the vicinity of the pipe or open hole. The change in wave speed of the probe pulses as the HALF induced strain wave oscillation propagates through the formation, as a function of the induced strain, may be used to determine the nonlinear elastic parameters , , , and A of the pore pressure, from which the pore pressure may be determined in the region of the HALF wave.

According to embodiments, an ultrasonic inspection apparatus comprises: an ultrasonic array probe having a plurality of ultrasonic elements; an estimated shape reflected wave arrival time calculator for computing the estimated shape reflected wave arrival time for the estimated shape reflected wave on the basis of the estimated sound velocity in the test object; an actual shape reflected wave arrival time extractor for extracting the actual shape reflected wave arrival time on the basis of the actual shape reflected wave; a shape reflected waves time difference calculator for computing the difference by subtracting the actual shape reflected wave arrival time from the estimated shape reflected wave arrival time as shape reflected waves time difference; and a delay time calculator for computing the delay times for mutually shifting the timings of ultrasonic wave transmission and ultrasonic wave reception by the ultrasonic elements, considering the shape reflected waves time differences.

A method and device are provided for determining a mode of detection of an element that reflects ultrasonic waves, wherein it comprises at least the following steps: For each point P of a given volume Zr, determining an ultrasonic field value A.sub.ij.sup.m (P) for N emitter-receiver pairs (i, j) and for one detection mode m,

computing a number

[00001]$C^m\left(P,\stackrel{.fwdarw.}{n}\right)=\underset{i,j=1}{\overset{N}{.Math.}}.Math..Math.c_{\mathrm{ij}}^m\left(P,\stackrel{.fwdarw.}{n}\right)$

of reflections of the wave where

[00002]$c_{\mathrm{ij}}^m=\{\begin{array}{cc}1& \mathrm{if}.Math..Math..Math.{\stackrel{.fwdarw.}{n}}_{\mathrm{ij}}^m\left(P\right).Math.\stackrel{.fwdarw.}{n}.Math.=1\\ 0& \mathrm{if}.Math..Math.\mathrm{not}\end{array}$

with {right arrow over (n)}.sub.ij.sup.m(P) the normal formed by the forward direction {right arrow over (d)}.sub.i and the backward direction {right arrow over (d)}.sub.j of the ultrasonic wave emitted and reflected by the reflecting element, computing the energy value E.sup.m(P,{right arrow over (n)}) for each point P of the zone Zr, with {right arrow over (n)} and for a plurality of modes m with

[00003]

A method for determining a corrected value for a viscosity-dependent sonic velocity in a fluid under test includes generating and transmitting sound pulses to the fluid under test, registering the sound pulses after traversing a predetermined measuring distance in the fluid under test, and ascertaining a first arrival of a first sound pulse received after traversing the measuring distance and determining the transit time of the first received sound pulse in the fluid under test. A viscosity is predetermined or ascertained for the fluid under test, and a transit time of the first received sound pulse and the viscosity are used to determine the sonic velocity in the fluid under test. An apparatus for determining a corrected value for a viscosity-dependent sonic velocity in a fluid under test is also provided.

It is proposed a method for detecting a malfunction of a dual-sensing system for sensing a fluid mixture stored in a tank of a vehicle, the dual-sensing system being able to provide values of two physical quantities, i.e. one quantity indicative of a concentration of a constituent of the fluid mixture within the tank and one quantity indicative of a level of the fluid mixture within the tank, the dual-sensing system comprising: a first ultrasound subsystem for determining the value of the physical quantity indicative of the concentration of the constituent of the fluid mixture; and a second ultrasound subsystem for determining, based on the value provided by the first ultrasound subsystem, the value of the physical quantity indicative of the level of the fluid mixture within the tank, the method comprises the steps of: when key is off: memorizing the last known value of a first physical quantity out of the two physical quantities and the last known value of a second physical quantity out of the two physical quantities; when key is on, sequentially: having new values of the two physical quantities provided by the dual-sensing system; if the last known value of the first physical quantity is not the same as the new value of the first physical quantity, stop the carrying out of the method; if the last known value of the second physical quantity is not the same as the new value of the second physical quantity, emitting a signal indicative of malfunctioning.

It is proposed a method for detecting a malfunction of a dual-sensing system for sensing a fluid mixture stored in a tank of a vehicle, the dual-sensing system being able to provide values of two physical quantities, i.e. one quantity indicative of a concentration of a constituent of the fluid mixture within the tank and one quantity indicative of a level of the fluid mixture within the tank, the dual-sensing system comprising: a first ultrasound subsystem for determining the value of the physical quantity indicative of the concentration of the constituent of the fluid mixture; and a second ultrasound subsystem for determining, based on the value provided by the first ultrasound subsystem, the value of the physical quantity indicative of the level of the fluid mixture within the tank, the method comprises the steps of: when key is off: memorizing the last known value of a first physical quantity out of the two physical quantities and the last known value of a second physical quantity out of the two physical quantities; when key is on, sequentially: having new values of the two physical quantities provided by the dual-sensing system; if the last known value of the first physical quantity is not the same as the new value of the first physical quantity, stop the carrying out of the method; if the last known value of the second physical quantity is not the same as the new value of the second physical quantity, emitting a signal indicative of malfunctioning.

Various arrangements for detecting an object using a passive infrared (PIR) sensor module of a sensor device. A PIR data stream may be received from the PIR sensor module indicative of measurements performed by the PIR sensor module. An indication may be received from a transceiver that identifies a beginning of the data transmission. A portion of the PIR data stream may be blanked in response to receiving the indication of the beginning of the data transmission, the portion of the PIR data stream corresponding to a defined time duration. A presence of an object may be determined using the PIR data stream, excluding the blanked portion.