Dynamische Venenfunktionstests auf dem Prüfstand

Phlebologie ◽  
2002 ◽  
Vol 31 (04) ◽  
pp. 85-90 ◽  
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.

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

1982 ◽  
Vol 47 (02) ◽  
pp. 141-144 ◽  
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.

Metal Strain Gauge Pressure Sensor Using SiO2/Si3N4 Diaphragm

2019 ◽  
Vol 139 (4) ◽  
pp. 63-68
Author(s):  
Hiroshi Nakano ◽  
Masahiro Matsumoto ◽  
Yasuo Onose ◽  
Kazuhiro Ohta
Keyword(s):  
Pressure Sensor ◽  
Strain Gauge ◽  
Gauge Pressure ◽  
Metal Strain

TWO METHODS FOR CALIBRATION OF STRAIN-GAUGE BALANCES USING TSAGI BALANCE CALIBRATION MACHINES

2017 ◽  
Vol 48 (2) ◽  
pp. 187-197 ◽  
Author(s):  
Valerii Semyonovich Volobuyev ◽  
Anton Roaldovich Gorbushin ◽  
Iraida Alekseevna Sudakova ◽  
V. I. Tikhomirov
Keyword(s):  
Strain Gauge ◽  
Balance Calibration

APPLICATION OF THE METHOD SPRINGY DEFORMATIONS OF BARREL DURING SHOT FOR DETERMINING THE INITIAL VELOCITY OF THE SHELL (MINE)

2019 ◽  
Vol 1 (12) ◽  
pp. 75-80
Author(s):  
Ye. Didenko ◽  
O. Stepanenko
Keyword(s):  
Strain Gauge ◽  
Initial Velocity ◽  
Radial Direction ◽  
Fire Control ◽  
Automatic Control Systems ◽  
Measurement Results ◽  
Initial Resistance ◽  
The Moment ◽  
The Many ◽  
Effective Use

One of the indicators of the effective use of artillery is the accuracy of the fire impact on the objects of enemy. The accuracy of the artillery is achieved by completing the implementation of all measures for the preparation of shooting and fire control. Main measures of ballistic preparation are to determine and take into account the summary deviation of the initial velocity. The existing procedure for determining the summary deviation of the initial velocity for the check (main) cannon of battery leads to accumulation of ballistic preparation errors. The supply of artillery units with means of determining the initial speed of the projectile is insufficient. Among the many known methods for measuring the initial velocity, not enough attention was paid to the methods of analyzing the processes that occur during a shot in the "charge-shell-barrel" system. Under the action of the pressure of the powder gases in the barrel channel and the forces of the interaction of the projectile with the barrel there are springy deformations in the radial direction. To measure springy deformations it is advisable to use strain gauge sensors. Monitoring of deformation in a radial direction by time can be used to determine the moment of passing a projectile past the strain gauge mounted on the outer surface of the barrel. In the case of springy deformations, the initial resistance of the sensor varies in proportion to its value. The speed of the shell (mine) in the barrel can be determined by time between pulses of signals obtained from strain gauges located at a known distance from each other. The simplicity of the proposed method for measuring the initial velocity of an artillery shell provides an opportunity for equipping each cannon (mortar) with autonomous means for measuring the initial velocity. With the simultaneous puting into action of automatic control systems can be automatically taking into account the measurement results. This will change the existing procedure for determining the total deviation of the initial velocity and improve the accuracy, timeliness and suddenness of the opening of artillery fire, which are components of its efficiency.

Automatic Assembly System of Strain Gauge Based on Deviation Model

ROBOT ◽  
2013 ◽  
Vol 35 (5) ◽  
pp. 589
Author(s):  
Dechun ZHENG ◽  
Yongping ZHANG ◽  
Guojun LI
Keyword(s):  
Strain Gauge ◽  
Assembly System ◽  
Automatic Assembly

Evaluation of a Hand-Held Frictional Strain Gauge.

1987 ◽  
Author(s):  
M. G. Stimson ◽  
J. G. Sparrow
Keyword(s):  
Strain Gauge
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