Electronic Speckle Pattern Interferometry of the Vibrating Larynx

1995 ◽  
Vol 104 (1) ◽  
pp. 5-12 ◽  
Author(s):  
Glendon M. Gardner ◽  
Michelle Conerty ◽  
James Castracane ◽  
Steven M. Parnes
Keyword(s):  
Real Time ◽  
Quantitative Research ◽  
Speckle Pattern ◽  
Three Dimensional ◽  
Vocal Folds ◽  
Digital Data ◽  
Electronic Speckle Pattern Interferometry ◽  
Clinical Tool ◽  
Digital Hardware ◽  
Laser Holography

Laser holography is a technique that creates a three-dimensional image of a static object. This technique can be applied to the analysis of vibrating structures. Electronic speckle pattern interferometry uses a laser for illumination of the vibrating object and solid state detectors and digital hardware technology for capturing and processing the image in real time. This was performed on a human cadaver larynx and is the first time an interferogram of vibrating vocal cords has ever been obtained. Dark and bright interference fringes are seen that represent the vibratory motion of the vocal folds. These are presented in still photos as well as real-time on videotape. This method can provide advantages over current techniques of laryngeal study: it is sensitive to motion in the vertical dimension, and the digital data can be quantitatively analyzed. Application of this technique to study the larynx should eventually be a valuable clinical tool and provide quantitative research data.

A Study on the Vibration Characteristics of Symmetry and Asymmetry Laminated Composite Materials by Using ESPI

2007 ◽  
Vol 353-358 ◽  
pp. 2366-2370
Author(s):  
Kyung Min Hong ◽  
Young June Kang ◽  
Nak Kyu Park ◽  
Weon Jae Ryu
Keyword(s):  
Composite Materials ◽  
Real Time ◽  
Optical Measurement ◽  
Speckle Pattern ◽  
Laminated Composite ◽  
Vibration Characteristics ◽  
Electronic Speckle Pattern Interferometry ◽  
Full Field ◽  
Reinforced Plastics ◽  
Laminated Composite Materials

The ESPI (Electronic Speckle Pattern Interferometry) is a real-time, full-field, non-destructive optical measurement technique. In this study, ESPI was proposed for the purpose of vibration analysis for new and composite materials. Composite materials have various complicated characteristics according to the materials, orientations, stacking sequences of the ply and boundary conditions. Therefore, it was difficult to analyze composite materials. For efficient use of composite materials in engineering applications the dynamic behavior (i.e., natural frequencies and nodal patterns) should be informed. With the use of Time-Average ESPI, one could analyze vibration characteristics of composite material by real time easily. We manufactured two kinds of laminated composites (i.e., symmetry and asymmetry) which were consisted of CFRP (Carbon Fiber Reinforced Plastics) and the shape of the test piece was of rectangular form.

scholarly journals In Vivo Computed Tomography as a Research Tool to Investigate Asthma and COPD: Where Do We Stand?

2012 ◽  
Vol 2012 ◽  
pp. 1-11 ◽  
Author(s):  
Gaël Dournes ◽  
Michel Montaudon ◽  
Patrick Berger ◽  
François Laurent
Keyword(s):  
Computed Tomography ◽  
Quantitative Research ◽  
Three Dimensional ◽  
Lung Parenchyma ◽  
Airway Disease ◽  
Bronchial Tree ◽  
Research Tool ◽  
Airway Wall ◽  
Clinical Tool

Computed tomography (CT) is a clinical tool widely used to assess and followup asthma and chonic obstructive pulmonary disease (COPD) in humans. Strong efforts have been made the last decade to improve this technique as a quantitative research tool. Using semiautomatic softwares, quantification of airway wall thickness, lumen area, and bronchial wall density are available from large to intermediate conductive airways. Skeletonization of the bronchial tree can be built to assess its three-dimensional geometry. Lung parenchyma density can be analysed as a surrogate of small airway disease and emphysema. Since resident cells involve airway wall and lung parenchyma abnormalities, CT provides an accurate and reliable research tool to assess their role in vivo. This litterature review highlights the most recent advances made to assess asthma and COPD with CT, and also their drawbacks and the place of CT in clarifying the complex physiopathology of both diseases.

Investigation of three-dimensional deformations of corroding natural stones using electronic speckle pattern interferometry

1990 ◽  
Author(s):  
Gerd Guelker ◽  
Olaf Haack ◽  
Klaus D. Hinsch ◽  
Claudia Hoelscher ◽  
Juergen Kuls ◽  
...  
Keyword(s):  
Speckle Pattern ◽  
Three Dimensional ◽  
Electronic Speckle Pattern Interferometry ◽  
Natural Stones

A Study on Measurement of Welding Residual Stress Using ESPI System

2006 ◽  
Vol 324-325 ◽  
pp. 859-862 ◽  
Author(s):  
Kyung Su Kim ◽  
Seung Bok Choi ◽  
Jang Hyun Lee ◽  
Seong Mo Park ◽  
Beom Il Kim ◽  
...  
Keyword(s):  
Residual Stresses ◽  
Speckle Pattern ◽  
Three Dimensional ◽  
Welding Residual Stress ◽  
Electronic Speckle Pattern Interferometry ◽  
Fe Model ◽  
Analysis Model ◽  
Element Analysis ◽  
The Difference ◽  
Welding Procedure

In this study, an experimental method has been studied to measure the residual stresses on a specimen with I-groove weldment. The specimens were extracted from I-groove weldment which was joined by SAW (Submerged Arc Welding) with CO2 shield gas. A FEA (Finite Element Analysis) model was developed for the estimation of the residual stresses for the specimen. Measurements were carried out using ESPI(Electronic Speckle Pattern Interferometry) system which can measure the strain distribution on the surface of specimen. The residual stresses were estimated by the value of strain measured by ESPI system. Strain gages were added to evaluate the accuracy of ESPI system. In addition, a three-dimensional FE model was used to estimate the residual stresses generated by the welding procedure. A thermal elasto-plastic analysis was performed by the FEA. The stresses measured by the experiments were compared with the results of FEA. Also, discussed are the difference and agreement between the stresses obtained by experiments and FEA, respectively.

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