Correlation signal processing for determination of the spatial distributions of temperature and acoustic characteristics of the medium

In the last years, many analyses from acoustic signal processing have been used for different applications. In most cases, these sensor systems are based on the determination of times of flight for signals from every transducer. This paper presents a flat plate generalization method for impact detection and location over linear links or bars-based structures. The use of three piezoelectric sensors allow to achieve the position and impact time while the use of additional sensors lets cover a larger area of detection and avoid wrong timing difference measurements. An experimental setup and some experimental results are briefly presented.

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Determination of Hurst exponent by optical signal processing applied on surface roughness measurements

10.1117/12.845799 ◽

2009 ◽

Author(s):

José Antonio Marbán Salgado ◽

Oscar Sarmiento Martínez ◽

Darwin Mayorga Cruz ◽

Jorge Uruchurtu Chavarín

Keyword(s):

Surface Roughness ◽

Signal Processing ◽

Hurst Exponent ◽

Optical Signal Processing ◽

Optical Signal ◽

Roughness Measurements

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Analysis of Stall Precursors and Determination of Optimum Signal Processing Methods for an LM-2500 Gas Turbine

Volume 7: Education; Industrial and Cogeneration; Marine; Oil and Gas Applications ◽

10.1115/gt2008-50575 ◽

2008 ◽

Author(s):

Knox T. Millsaps ◽

Gustave C. Dahl ◽

Daniel E. Caguiat ◽

Jeffrey S. Patterson

Keyword(s):

Time Series ◽

Signal Processing ◽

Gas Turbine ◽

Rotor Speed ◽

Processing Methods ◽

Turbine Engine ◽

Pressure Signal ◽

Time Series Analyses ◽

Signal Processing Methods

This paper presents an analysis of data taken from several stall initiation events on a GE LM-2500 gas turbine engine. Specifically, the time series of three separate pressure signals located at compressor stages 3, 6, and 15 were analyzed utilizing various signal processing methods to determine the most reliable indicator of incipient stall for this engine. The spectral analyses performed showed that rotating precursor waves traveling around the annulus at approximately half of the rotor speed were the best indicators. Non-linear chaotic time series analyses were also used to predict stall, but it was not as reliable an indicator. Several algorithms were used and it was determined that stall wave perturbations can be reliably identified about 900 revolutions prior to the stall. This work indicates that a single pressure signal located at stage 3 on an LM-2500 gas turbine is sufficient to provide advance warning of more than 2 seconds prior to the fully developed stall event.

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Determination of tellurium in urine by hydride generation atomic absorption spectrometry with derivative signal processing

Analytica Chimica Acta ◽

10.1016/s0003-2670(01)01283-1 ◽

2001 ◽

Vol 448 (1-2) ◽

pp. 145-149 ◽

Cited By ~ 13

Author(s):

Jing Ha ◽

Han-Wen Sun ◽

Jian-Min Sun ◽

De-Qiang Zhang ◽

Li-Li Yang

Keyword(s):

Signal Processing ◽

Atomic Absorption Spectrometry ◽

Atomic Absorption ◽

Hydride Generation ◽

Absorption Spectrometry

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The Estimation of Long-Range Internal Stress Fields by Spectral-Acoustic Method

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1013.121 ◽

2014 ◽

Vol 1013 ◽

pp. 121-126 ◽

Cited By ~ 1

Author(s):

Aleksandr Smirnov ◽

Nikolai Ababkov ◽

Aleksandra Glinka

Keyword(s):

Conceptual Model ◽

Physical And Mechanical Properties ◽

Acoustic Method ◽

Electron Microscopic ◽

Limiting State ◽

Acoustic Characteristics ◽

Complex Criterion ◽

Microscopic Studies ◽

Hazardous Production

A conceptual model consisting of diagrams, text and terminology dictionary, made in a formalized way and representations of functions, each of which reflects the real state of the long-running metal at all stages of the life cycle. Based on the developed conceptual model, analysis of the results of electron microscopic studies measuring the acoustic characteristics and determination of physical and mechanical properties of the complex criterion limiting state long working metal technical devices hazardous production facilities.

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