Dynamic torsion of viscoelastic cylindrical rods

1976 ◽  
Vol 11 (3) ◽  
pp. 408-417
Author(s):  
I. A. Kiiko ◽  
M. Kh. Il'yasov
Keyword(s):  
Dynamic Torsion

Normal thrust in dynamic torsion for rubber-like materials

1961 ◽  
Vol 1 (4-6) ◽  
pp. 602-602
Author(s):  
A. F. H. Ward ◽  
G. M. Jenkins
Keyword(s):  
Dynamic Torsion

Measurement of the Elastic Moduli of Structural Adhesives by a Resonant Bar Technique

1976 ◽  
Vol 18 (3) ◽  
pp. 149-158 ◽  
Author(s):  
R. D. Adams ◽  
J. Coppendale
Keyword(s):  
Thin Film ◽  
Elastic Moduli ◽  
Dynamic Tests ◽  
Structural Adhesives ◽  
Young’S Moduli ◽  
Epoxy Adhesives ◽  
Dynamic Torsion ◽  
Static And Dynamic Tests

A method of measuring the dynamic torsion and Young's moduli of a thin film of adhesive is described. The accuracy of the technique and its suitability for structural adhesives is discussed. Values of modulus obtained using this method are compared with values obtained from static and dynamic tests on bulk specimens of three epoxy adhesives.

scholarly journals P971 The echocardiographic phenotype in patients with cardiac amyloidosis and heart failure with preserved ejection fraction

2020 ◽  
Vol 21 (Supplement_1) ◽  
Author(s):  
M D M Perez Gil ◽  
V Mora Llabata ◽  
A Saad ◽  
A Sorribes Alonso ◽  
V Faga ◽  
...  
Keyword(s):  
Heart Failure ◽  
Ejection Fraction ◽  
Cardiac Amyloidosis ◽  
Nyha Class ◽  
Left Ventricular ◽  
Left Ventricular Ejection ◽  
Control Group ◽  
Ventricular Ejection Fraction ◽  
Apical Rotation ◽  
Dynamic Torsion

Abstract BACKGROUND New echocardiographic phenotypes of heart failure (HF) are focused on myocardial systolic involvement of the left ventricle (LV), either endocardial and/or transmural. PURPOSE. To study the pattern of myocardial involvement in patients (p) with HF with preserved left ventricular ejection fraction (pLVEF) and cardiac amyloidosis (CA). METHODS. Comparative study of 16 p with CA and HF with pLVEF, considering as cut point LVEF > 50%, in NYHA class ≥ II / IV, and a control group of 16 healthy people. Longitudinal Strain (LS) and Circumferential Strain (CS) were calculated using 2D speckle-tracking echocardiography, along with Mitral Annulus Plane Systolic Excursion (MAPSE) and Base-Apex distance (B-A). Also, the following indexes were calculated: Twist (apical rotation + basal rotation, º); Classic Torsion (TorC): (twist/B-A, º/cm); Torsion Index (Tor.I): (twist/MAPSE, º/cm) and Deformation Index (Def.I): (twist/LS, º). We suggest the introduction of these dynamic torsion indexes as Tor.I and Def.I that include twist per unit of longitudinal systolic shortening of the LV instead of using TorC which is the normalisation of twist to the end-diastolic longitudinal diameter of the LV. RESULTS There were no differences of age between the groups (68.2 ± 11.5 vs 63.7 ± 2.8 years, p = 0.14). Global values of LS and CS were lower in p with CA indicating endocardial and transmural deterioration during systole, while TorC and Twist of the LV remained conserved in p with CA. However, there is an increase of dynamic torsion parameters such as Tor.I and Def.I that show an increased Twist per unit of longitudinal shortening of the LV in the CA group (Table). CONCLUSIONS In p with CA and HF with pLVEF, the impairment of LS and CS indicates endocardial and transmural systolic dysfunction. In these conditions, LVEF would be preserved at the expense of a greater dynamic torsion of the LV. Table LS (%) CS (%) Twist (º) TorC (º/cm) Tor.I (º/cm) Def.I (º/%) CA pLVEF (n = 16) -11.7 ± 4.2 17.2 ± 4.8 19.8 ± 8.3 2.5 ± 1.1 27.7 ± 13.5 -1.8 ± 0.9 Control Group (n = 15) -20.6 ± 2.5 22.7 ± 4.9 21.7 ± 6.1 2.7 ± 0.8 16.4 ± 4.7 -1.0 ± 0.3 p < 0.001 < 0.01 0.46 0.46 < 0.01 < 0.01 Dynamic Torsion Indexes and Classic Torion Parameters in pLVEF CA patients vs Control group.

Unusual magnetic phenomena in dynamic torsion studies of fullerene Rb3C60

2020 ◽  
Vol 46 (2) ◽  
pp. 195-206
Author(s):  
J. Chigvinadze ◽  
S. Ashimov ◽  
A. Dolbin ◽  
G. Mamniashvili
Keyword(s):  
Dynamic Torsion ◽  
Magnetic Phenomena

The exterior gravitational field of a charged spinning source in the poincaré gauge theory: A Kerr-newman metric with dynamic torsion

1988 ◽  
Vol 128 (5) ◽  
pp. 245-250 ◽  
Author(s):  
Peter Baekler ◽  
Metin Gürses ◽  
Friedrich W. Hehl ◽  
J.Dermott McCrea
Keyword(s):  
Gravitational Field ◽  
Gauge Theory ◽  
Dynamic Torsion

scholarly journals Torsion Dynamic Behaviour of the Ship Hull Made out of Layered Composites

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Ionel Chirica
Keyword(s):  
Composite Plates ◽  
Past Research ◽  
Layered Composite ◽  
Ship Hull ◽  
Scale Model ◽  
Behavioral Characteristics ◽  
Container Ship ◽  
Layered Composites ◽  
Dynamic Torsion ◽  
Software Code

This paper addresses the dynamic torsion behaviour of the ship hull with very large open decks. A short overview of the past research is presented, and several key findings and behavioral characteristics are discussed. In the paper, the author is focusing on the dynamic part of a new macroelement model used for torsion dynamic analysis of the ship hull made of composite materials. The numerical analysis (using two methods, one of them being a new proposed method) and experiments are developed on a simplified typical hull of a container ship. The torsion analysis is performed on a scale model of a container ship, made of layered composite plates, and the first 5 natural frequencies are determined. The results obtained with the proposed numerical method (software code TORS, made by the author) are compared with the results obtained with FE analysis and with the experiments done on the physical model.

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