Investigation on the Coupling Effect Induced by Bilayer Structure of Thin Au Film and Graphene Nanoplates for Strain Gauge

A tribotester with an integrated load sensor based on a strain gauge is typically used to measure the friction coefficient generated by the contact-related sliding motion of two objects. Since the friction coefficient is obtained by dividing the measured friction force by the applied normal force, the normal and friction forces must be measured for accurate analysis. In this study, a tribotester was used to measure the displacement of a cantilever tip using the fiberoptic sensor in a non-contact method. The friction coefficient measurement using the fiberoptic sensor was proven to be valid by calibrating the tip displacement due to normal/friction forces after designing a basic structural cantilever tip based on experiments and simulation analyses. The results obtained by using the fiberoptic sensor-cantilever tip-based tribotester were compared with those obtained using commercial and/or custom-built tribotesters under the same conditions. By designing various shapes of cantilever tips and using simulation analysis, the calibrations of the normal/friction forces and tip displacement could be verified and the coupling effect was evaluated. The performance and reliability of the fiberoptic sensor-cantilever tip-based tribotester, which can be used to determine the normal/friction forces by non-contact displacement measurements without a strain gauge, were verified.

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Electron-molecular vibration coupling effect on the Raman spectrum of organic charge transfer salts

Journal de Physique IV (Proceedings) ◽

10.1051/jp4:2004114037 ◽

2004 ◽

Vol 114 ◽

pp. 153-155 ◽

Cited By ~ 5

Author(s):

Kaoru Yamamoto ◽

Kyuya Yakushi

Keyword(s):

Raman Spectrum ◽

Charge Transfer ◽

Coupling Effect ◽

Molecular Vibration ◽

Charge Transfer Salts ◽

Vibration Coupling

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Dynamische Venenfunktionstests auf dem Prüfstand

Phlebologie ◽

10.1055/s-0037-1621393 ◽

2002 ◽

Vol 31 (04) ◽

pp. 85-90 ◽

Cited By ~ 2

Author(s):

H.-M. Häfner ◽

H. Bablich ◽

G. Rassner ◽

M. Jünger ◽

A. Steins

Keyword(s):

Strain Gauge ◽

Automatische Auswertung

Zusammenfassung Ziel: Überprüfung der Korrelation der photooptischen Venenfunktionstests Lichtreflexionsrheographie (LRR), digitale Photoplethysmographie (DPPG) und der Quecksilberdehnungsstreifen- Plethysmographie (Hg-strain gauge) mit der Phlebodynamometrie (PDM). Methode: Die simultane Messung von LRR, DPPG, Hg-strain gauge und PDM wurde an 34 Patienten mit chronischer venöser Insuffizienz in den klinischen Stadien I bis III nach Widmer an insgesamt 39 Unterschenkeln vorgenommen. Die Messungen erfolgten während Dorsalextension des Fußes in sitzender und während Plantarflexion des Fußes in stehender Position. Als Parameter für die Ermittlung des Korrelationskoeffizienten wurden die Wiederauffüllzeiten t0 und t1/2 sowie die venöse Abpumpleistung ermittelt. Ergebnisse: Unabhängig von Körperposition und Anlage von Tourniquets erreichten die Korrelationen für alle Messverfahren und Parameter Werte zwischen r = 0,76 (t0 LRR) und r = 0,05 (Abpumpleistung DPPG automatische Auswertung). Eine gute Korrelation von t0 wurde in stehender Körperposition unabhängig von der Anlage der Tourniquets beim Hg-strain gauge (r = 0,49) und LRR (r = 0,51) erreicht. Diese Korrelation verbesserte sich in sitzender Körperposition. Die schlechteste Korrelation wurde bei der DPPG ermittelt (r = 0,25 in stehender, r = 0,51 in sitzender Position). Eine Verbesserung der Korrelation wurde beim DPPG durch die manuelle Auswertung der Kurven erreicht. Schlussfolgerung: Sowohl die Wahl des Untersuchungsverfahrens wie auch das gewählte Belastungsprogramm können erhebliche Auswirkungen auf die Korrelation mit der PDM haben. Unsere Ergebnisse zeigen, dass bei der Bewertung der Wiederauffüllzeiten t0 und t1/2 der Hg-strain gauge und die LRR die höchste Korrelation bei Dorsalextension in sitzender Körperposition mit der PDM aufweisen.

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Diagnosis of Deep Vein Thrombosis by Combination of Doppler Ultrasound Flow Examination and Strain Gauge Plethysmography

Thrombosis and Haemostasis ◽

10.1055/s-0038-1657149 ◽

1982 ◽

Vol 47 (02) ◽

pp. 141-144 ◽

Cited By ~ 7

Author(s):

H Bounameaux ◽

B Krähenbühl ◽

S Vukanovic

Keyword(s):

Deep Vein Thrombosis ◽

Negative Predictive Value ◽

Doppler Ultrasound ◽

Strain Gauge ◽

Predictive Value ◽

Lower Limbs ◽

Vein Thrombosis ◽

Non Invasive ◽

Strain Gauge Plethysmography ◽

Deep Vein

SummaryDoppler ultrasound flow examination, strain gauge plethysmography and contrast venography were performed in 160 lower limbs of 80 in-patients. Deep vein thrombosis (DVT) was suspected in 87 limbs. Using measurement of venous stop-flow pressure, the Doppler method had an overall sensitivity of 83%. By combined use of Doppler and Plethysmography, sensitivity was increased to 96%. Specificity was 62% and 51%, respectively. With a positive and a negative predictive value of 80% and 73%, respectively, the combination of both non-invasive methods cannot reliably replace venography in the diagnosis of DTV, although all (40/40) thromboses proximal to or involving the popliteal segment were detected by either Doppler and Plethysmography or both.After exclusion of 14 patients (18%) suffering from conditions known to alter the results of these non-invasive methods, the positive predictive value of abnormal findings in both Doppler and Plethysmography was increased to 94% for suspected limbs, whilst negative predictive value of both negative Doppler and Plethysmography was 90%, allowing the avoidance of venography in these patients.

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An hourglass-type electromagnetic isolator with negative resistance electromagnetic shunt circuit

International Journal of Applied Electromagnetics and Mechanics ◽

10.3233/jae-209363 ◽

2020 ◽

Vol 64 (1-4) ◽

pp. 549-556

Author(s):

Yajun Luo ◽

Linwei Ji ◽

Yahong Zhang ◽

Minglong Xu ◽

Xinong Zhang

Keyword(s):

Vibration Isolation ◽

Electromechanical Coupling ◽

Coupling Effect ◽

Negative Resistance ◽

Isolation System ◽

Amplitude Vibration ◽

Vibration Responses ◽

The Stability ◽

Isolation Performance ◽

Shunt Circuit

The present work proposed an hourglass-type electromagnetic isolator with negative resistance (NR) shunt circuit to achieve the effective suppression of the micro-amplitude vibration response in various advanced instruments and equipment. By innovatively design of combining the displacement amplifier and the NR electromagnetic shunt circuit, the current new type of vibration isolator not only can effectively solve the problem of micro-amplitude vibration control, but also has significant electromechanical coupling effect, to obtain excellent vibration isolation performance. The design of the isolator and motion relationship is presented firstly. The electromechanical coupling dynamic model of the isolator is also given. Moreover, the optimal design of the NR electromagnetic shunt circuit and the stability analysis of the vibration isolation system are carried out. Finally, the simulation results about the transfer function and vibration responses demonstrated that the isolator has a significant isolation performance.

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