Laser ultrasonics-based material analysis system and method using matched filter processing

A system and associated processes monitor hand hygiene compliance. The system includes hand hygiene product dispensers positioned within areas of concern (AOC) in a facility in which hand hygiene events are to be monitored. The dispensers detect dispense events initiated at the dispenser and transmit a dispense event signal indicative that a dispense event occurred along with dispenser identification information. The system also includes a plurality of compliance badges, each worn by a different person in the facility. Each compliance badge receives dispense event signals corresponding dispenser identification information associated with dispense events initiated by the wearer of the compliance badge. The badges store dispense event records associated with each dispense event initiated by the wearer and thus keep track of all dispense events initiated by the wearer of the compliance badge. One or more data gathering stations positioned at various locations through the facility receive the dispense event information from the individual badges when they come within range. The dispense event information may then be transferred to a local or remote computer for analysis and reporting on hand hygiene events taking place within the facility.

Hand hygiene compliance monitoring

The existence and rate of corrosion in a section of a well tubing or well casing is determined and monitored by installing at predetermined locations as the string is placed in the well bore, sections of pipe (20) that have been fitted with an array of piezoelectric transducers (26) and a microprocessor (28) that controls signals going to and from each array of transducers and signals going to and received from controls and intrumentation apparatus located at the earth's surface. The microprocessors at varying locations along the string are electrically connected to the surface control and instrumentation apparatus by conductor cables and/or by wireless means using the pipe string as the conductive path for electrical signals.

Downhole well corrosion monitoring apparatus and method

This experimental work was aimed at investigating the monitoring of pitting corrosion by the acoustic emission (AE) technique, for pits developed by potentiostatic or galvanostatic polarization on two types of 316L austenitic stainless steels, in a 3% NaCl solution acidified to pH 2. The study of the evolution of AE global activity during the test showed the existence of a time delay before pits became emissive. This time delay and the AE events number rate measured during the propagation step of the pits are closely correlated with the sensitivity of the material towards pitting and with the polarization procedure. Moreover, the evolution of cumulative % of AE signals number versus selected acoustic parameters shows that rise time and counts number of signals appear to be discriminating acoustic parameters for monitoring pitting corrosion of austenitic stainless steels by acoustic emission technique in our experimental conditions, whatever the polarization procedure and the type of tested steel.

Monitoring pitting corrosion of AISI 316L austenitic stainless steel by acoustic emission technique: Choice of representative acoustic parameters

Disclosed herein is an interferometric-based materials analysis system (10) that employs a novel combination of laser beam shaping and pointing techniques, the use of a low cost, rugged, and compact diode laser (22) as a detection laser, and the use of signal processing techniques that compensate for inherent instabilities and short-term drift in the diode laser. A matched filter processing technique is disclosed for processing interferometrically-obtained data points from a target being analyzed. The matched filter technique is shown to be especially useful for detecting and analyzing Lamb modes within thin targets, such as a silicon wafer undergoing a rapid thermal processing cycle. Also disclosed is a method and apparatus for interferometrically monitoring a target to determine, in accordance with predetermined criteria, an occurrence of a period of time that is optimum for obtaining a data point. In response to detecting such a period an impulse source, such as an impulse laser (14), is triggered to launch an elastic wave within the target so that a data point can be obtained. A plurality of data points so obtained are subsequently processed, such as by the matched filter technique, to determine a property of interest of the target. The property of interest may be, by example, the temperature of the target or the metallurgical status of the target.

Laser ultrasonics-based material analysis system and method

An ultrasonic corrosion monitor is provided which produces an in situ measurement of the amount of corrosion of a monitoring zone or zones of an elongate probe placed in the corrosive environment. A monitoring zone is preferably formed between the end of the probe and the junction of the zone with a lead-in portion of the probe. Ultrasonic pulses are applied to the probe and a determination made of the time interval between pulses reflected from the end of the probe and the junction referred to, both when the probe is uncorroded and while it is corroding. Corresponding electrical signals are produced and a value for the normalized transit time delay derived from these time interval measurements is used to calculate the amount of corrosion.

R.J. Grossman

Papers

A High Resolution In Situ Ultrasonic Corrosion Monitor