Compensation of temporary errors of strain gauge resistor measuring devices

Abstract The dynamic error of devices belongs to the number of errors that are difficult to estimate. The mechanism for forming this error on the example of torsional torque dynamometersis briefly considered as the most common in the practice of research on the energy of agricultural machines. The limiting ratios of frequencies of external influences and natural vibrations of strain-measuring devices are given. Recommendations are made to reduce dynamic error in torque strain analysis. The present review and the accumulated experience of strain gauge research allows us to recommend some directions for reducing dynamic errors in torque measurements. In order for a strain gauge to keep up with changes in torque in its inertial characteristics, it must have the smallest torque inertia. In order to reduce the probability of high-frequency harmonics from the elastic vibrations of the strain gauge, it must be sufficiently rigid. From this point of view, strain rods, strain sprockets, etc., having a moment of inertia greater than that of the same gear parts, are irrational. Based on modern micromodules and power supplies, the system can have a small mass and have no significant effect on the inertial characteristic of the strain gauge.

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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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Transfer of the unit of oil volumetric moisture content to measuring devices

Automation Telemechanization and Communication in Oil Industry ◽

10.33285/0132-2222-2019-3(548)-5-8 ◽

2019 ◽

pp. 5-8

Author(s):

A.V. Voronenko ◽

◽

V.V. Averin ◽

D.E. Ushatkin ◽

◽

...

Keyword(s):

Moisture Content ◽

Measuring Devices ◽

Volumetric Moisture Content

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DEVELOPMENT OF MACAMI (MARI MEMBACA DAN MEMAHAMI) INSTRUMENT USING MACROMEDIA FLASH 8 IN PRIMARY SCHOOLS

JURNAL PAJAR (Pendidikan dan Pengajaran) ◽

10.33578/pjr.v4i3.7984 ◽

2020 ◽

Vol 4 (3) ◽

pp. 544

Author(s):

Ermaida Dewi

Keyword(s):

Reading Comprehension ◽

Primary School ◽

Product Design ◽

Primary Schools ◽

Measuring Instrument ◽

School Students ◽

Average Percentage ◽

Measuring Devices ◽

Comprehension Ability ◽

Feasibility Test

The background of this research is an instrument of learning for reading comprehension which in general is still dominated by an instrument in the form of print out which makes the students’ interest to read is reduced. In addition, this instrument is usually done manually or handwritten so that the students’ work must be corrected manually and require some time to get the results. This study aims to develop instruments or measuring devices for reading comprehension in the Primary School in Pekanbaru and find out the feasibility of measuring devices for reading comprehension skills. This product is Macromedia Flash 8 based namely "MaCaMi" which stands forMari Membaca dan Memahami. The research method used was the 4D model with four stages, such as the define stage, the design phase, the develop phase, and the dessiminate stage which is limited to the third stage. The data of this study were obtained from product design expert validation questionnaire, questionnaire validated by linguists, teacher response questionnaire and students response questionnaire. The data were generated quantitatively and analyzed by using the assessment criteria to determine the product quality. The results of this study showed the assessment of product design experts in draft 1 had an average percentage of 69.61% with the appropriate category then had increased in draft 2 to 90.56% with the very feasible category. The results of the feasibility test by linguists in draft 1 with had average percentage of 95.30% with the very feasible category then increased in draft 2 to 97.20% withn the very feasible category. The results of the teacher's response to the reading comprehension measuring instrument in the Primary School in Pekanbaru developed by researchers obtained an average percentage of 93.50% with a very good category and the results of students' responses to the measuring instrument obtained an average percentage of 89.90% with a category very good. Based on these results, it can be concluded that the product developed by researchers is feasible to be used as a measure of reading comprehension ability of primary school students.

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