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Journal articles on the topic 'Torsion constant'

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Published: 4 June 2021

Last updated: 6 February 2022

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1

MAHATO, PRASANTA. "GRAVITATIONAL CONSTANT AND TORSION." Modern Physics Letters A 17, no. 30 (September 28, 2002): 1991–98. http://dx.doi.org/10.1142/s0217732302008460.

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Riemann–Cartan space–time U4 is considered here. It has been shown that when we link topological Nieh–Yan density with the gravitational constant, we then obtain Einstein–Hilbert Lagrangian as a consequence.

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2

Ivey, Thomas A. "Minimal curves of constant torsion." Proceedings of the American Mathematical Society 128, no. 7 (March 2, 2000): 2095–103. http://dx.doi.org/10.1090/s0002-9939-00-05526-x.

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3

Mohazzabi, P., and B. M. Shefchik. "A universal relationship between spring constant and torsion constant." Journal of Physics and Chemistry of Solids 62, no. 4 (April 2001): 677–81. http://dx.doi.org/10.1016/s0022-3697(00)00205-5.

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4

Tweed, D., M. Fetter, D. Sievering, H. Misslisch, and E. Koenig. "Rotational kinematics of the human vestibuloocular reflex. II. Velocity steps." Journal of Neurophysiology 72, no. 5 (November 1, 1994): 2480–89. http://dx.doi.org/10.1152/jn.1994.72.5.2480.

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1. Gain matrices were used to quantify the three-dimensional vestibuloocular reflex (VOR) in five human subjects who were accelerated over 1 s and then spun at a constant 150 degrees/s for 29 s in darkness. Rotations were torsional, vertical and horizontal, about earth-vertical and earth-horizontal axes. 2. Elements on the main diagonal of the gain matrices were much smaller than the optimal value of -1, and torsional gain was weaker than vertical or horizontal. Off-diagonal elements, indicating cross talk, were minimal except for a small but consistent horizontal response to torsional head rotation. 3. Downward slow phases were more than twice as fast as upward at the start of rotation about both earth-vertical and earth-horizontal axes, but the asymmetry vanished later in the rotation. 4. During earth-vertical-axis rotation, all matrix elements decayed to zero. The main-diagonal torsional and vertical gains waned with time constants close to that of the cupula (6.7 and 7.3 s). Velocity storage prolonged the horizontal response to horizontal head rotation (time constant 14.2 s) but not the horizontal response to torsion (7.7 s). A simple explanation is that velocity storage acts on a central estimate of head motion that accurately distinguishes horizontal from torsional and that the inappropriate horizontal eye velocity response to torsion occurs because of cross talk downstream from velocity storage. 5. During earth-horizontal-axis rotation, the torsional, vertical, and horizontal main-diagonal elements declined, with time constants of 7.6, 8.2, and 7.9 s, to maintained nonzero values, all equal to about -0.1. Off-diagonal elements, including the horizontal response to torsion, decayed to zero, so that the otolith-driven reflex, late in the rotation, was equally strong in all dimensions and almost free of detectable cross talk. 6. The difference between gain curves over the course of earth-vertical- and earth-horizontal-axis rotations was not constant but increased with time, suggesting that the VOR response to earth-horizontal-axis rotation is not a simple sum of canal and otolith reflexes.

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5

Popławski, N. J. "Cosmological constant from quarks and torsion." Annalen der Physik 523, no. 4 (February 1, 2011): 291–95. http://dx.doi.org/10.1002/andp.201000162.

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6

Bates, Larry M., and O. Michael Melko. "On curves of constant torsion I." Journal of Geometry 104, no. 2 (July 20, 2013): 213–27. http://dx.doi.org/10.1007/s00022-013-0166-2.

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7

De Sabbata, Venzo, and C. Sivaram. "Torsion and the cosmological constant problem." Astrophysics and Space Science 165, no. 1 (March 1990): 51–55. http://dx.doi.org/10.1007/bf00653656.

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8

CALINI, ANNALISA, and THOMAS IVEY. "BÄCKLUND TRANSFORMATIONS AND KNOTS OF CONSTANT TORSION." Journal of Knot Theory and Its Ramifications 07, no. 06 (September 1998): 719–46. http://dx.doi.org/10.1142/s0218216598000383.

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The Bäcklund transformation for pseudospherical surfaces, which is equivalent to that of the sine-Gordon equation, can be restricted to give a transformation on space curves that preserves constant torsion. We study its effects on closed curves (in particular, elastic rods) that generate multiphase solutions for the vortex filament flow (also known as the Localized Induction Equation). In doing so, we obtain analytic constant-torsion representatives for a large number of knot types.

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9

SCHÜCKER, THOMAS, and ANDRÉ TILQUIN. "TORSION, AN ALTERNATIVE TO THE COSMOLOGICAL CONSTANT?" International Journal of Modern Physics D 21, no. 13 (December 2012): 1250089. http://dx.doi.org/10.1142/s0218271812500897.

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We confront Einstein–Cartan's theory with the Hubble diagram and obtain a negative answer to the question in the title. Contrary findings in the literature seem to stem from an error in the field equations.

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10

Saulnier, Michael S., and David Frisch. "Measurement of the gravitational constant without torsion." American Journal of Physics 57, no. 5 (May 1989): 417–20. http://dx.doi.org/10.1119/1.16013.

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11

Hammond, Richard T. "Upper limit on the torsion coupling constant." Physical Review D 52, no. 12 (December 15, 1995): 6918–21. http://dx.doi.org/10.1103/physrevd.52.6918.

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12

Ross, D. K. "Planck's constant, torsion, and space-time defects." International Journal of Theoretical Physics 28, no. 11 (November 1989): 1333–40. http://dx.doi.org/10.1007/bf00671851.

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13

Arroyo, Josu, Óscar J. Garay, and Álvaro Pámpano. "Binormal Motion of Curves with Constant Torsion in 3-Spaces." Advances in Mathematical Physics 2017 (2017): 1–8. http://dx.doi.org/10.1155/2017/7075831.

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We study curve motion by the binormal flow with curvature and torsion depending velocity and sweeping out immersed surfaces. Using the Gauss-Codazzi equations, we obtain filaments evolving with constant torsion which arise from extremal curves of curvature energy functionals. They are “soliton” solutions in the sense that they evolve without changing shape.

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14

Cirilo-Lombardo, D. J., and V. D. Gershun. "Integrable hydrodynamic equations for initial chiral currents and infinite hydrodynamic chains from WZNW model and string model of WZNW type with SU(2), SO(3), SP(2), SU(∞), SO(∞), SP(∞) constant torsions." International Journal of Modern Physics A 29, no. 24 (September 29, 2014): 1450134. http://dx.doi.org/10.1142/s0217751x14501346.

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The WZNW and string models are considered in terms of the initial and invariant chiral currents assuming that the internal and external torsions coincide (anticoincide) and they are the structure constants of the SU(n), SO(n), SP(n) Lie algebras. These models are the auxiliary problems in order to construct integrable equations of hydrodynamic type. It was shown that the WZNW and string models in terms of invariant chiral currents are integrable for the constant torsion associated with the structure constants of the SU(2), SO(3), SP(2) and SU(3) algebras only. The equation of motion for the density of the first Casimir operator was obtained in the form of the inviscid Burgers equation. The solution of this equation is presented through the Lambert function. Also, a new equation of motion for the initial chiral current was found. The integrable infinite hydrodynamic chains obtained from the WZNW and string models are given in terms of invariant chiral currents with the SU(2), SO(3), SP(2) and with SU(∞), SO(∞), SP(∞) constant torsions. Also, the equations of motion for the density of any Casimir operator and new infinite-dimensional equations of hydrodynamic type for the initial chiral currents through the symmetric structure constant of SU(∞), SO(∞), SP(∞) algebras are obtained.

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15

Li, Hong Yan, and Xiu Li Li. "Finite Element Analysis of the Cylindrical Helical Torsional Spring." Applied Mechanics and Materials 397-400 (September 2013): 633–36. http://dx.doi.org/10.4028/www.scientific.net/amm.397-400.633.

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Stress of the cylindrical helical torsion spring is researched with finite element method when torsional degree changes. For spring has great resilience, large deformation effect is considered in the simulations. Analysis on the stiffness shows that the model built is credible, although torsional stiffness is not constant for large torsional angle, the strength is enough whose variation trend is consistent with the spring stiffness with different working torsional angle.

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16

KOUFOGIORGOS, T., and C. TSICHLIAS. "CONTACT METRIC THREE-MANIFOLDS WITH CONSTANT SCALAR TORSION." Journal of the Australian Mathematical Society 107, no. 02 (October 29, 2018): 234–55. http://dx.doi.org/10.1017/s1446788718000265.

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In this paper we study three-dimensional contact metric manifolds satisfying $\Vert \unicode[STIX]{x1D70F}\Vert =\text{constant}$ . The local description, as well as several global results and new examples of such manifolds are given.

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17

Gershun, V. D. "Integrable string models with constant SU(3) torsion." Physics of Particles and Nuclei Letters 8, no. 3 (May 2011): 293–98. http://dx.doi.org/10.1134/s1547477111030083.

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18

Pitatzis, N., G. Savaidis, A. Savaidis, and Chuan Zeng Zhang. "Fatigue Analysis of Notched Shafts under Multiaxial Synchronous Cyclic Loading." Key Engineering Materials 348-349 (September 2007): 233–36. http://dx.doi.org/10.4028/www.scientific.net/kem.348-349.233.

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Parametrical elastic-plastic finite element analyses of a circumferentially notched shaft subjected to multiaxial synchronous fatigue loading are performed considering two load combinations: (1) constant tension with cyclic torsion and (2) constant torsion with cyclic tensioncompression. The load amplitudes and the mean loads are varied to investigate their influences on the local stress-strain responses. The Multilayer Plasticity Model of Besseling in conjunction with the von Mises yield criterion is applied to describe the elastic-plastic material behavior. Coarse and fine meshes as well as three different types of multilinear approximations (twenty-, five- and threesegments) of the material stress-strain curve are used. Numerical results are presented to reveal the mutual interactions between the applied normal and torsional loads and the stress-strain response at the notch-root.

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19

Nezdanov, Kirill, Igor Garkin, and Nikolay Laskov. "Increasing the Moment of Inertia of Crane Rails Torsional." Applied Mechanics and Materials 865 (June 2017): 188–91. http://dx.doi.org/10.4028/www.scientific.net/amm.865.188.

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This article is devoted to extreme increase in the moments of inertia of crane rails torsional strongly influence the endurance of crane girders. We investigate increase in moment of inertia of the rail under torsion with increasing thickness of the walls and shelves of thick-walled I-section profile in the square until its transformation into a square profile. It was found that the transformation of the profile of a monolithic solid square increases the moment of inertia of the torsion Jkr, cm4 to 3,1075 times and reaches its extreme. A cross-sectional area remains constant (const). Crane rails with a high moment of inertia for torsion provides significant economic benefits, and significantly reduces the operating costs of the enterprise.

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20

XI, PING. "ON THE LATE-TIME EVOLUTION IN A TORSION COSMOLOGY." International Journal of Modern Physics: Conference Series 07 (January 2012): 184–93. http://dx.doi.org/10.1142/s2010194512004254.

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In this paper, we study the late-time behavior of a torsion cosmology. We show that there is the late-time de Sitter attractor when the torsion parameter a1belongs to [Formula: see text], which indicates the late-time behaviors of torsion cosmology insensitive to the initial condition and thus alleviates the fine-tuning problem. Furthermore, we discuss the evolution of statefinder parameters for torsion cosmology in the four different ranges of a1, and find their typical characteristic different from the other cosmological models. Most of importance, we obtain three kinds of solutions with a constant affine scalar curvature and a kind of expression with the non-constant curvature. Using these expressions, we shall be able to predict the evolution over the late-time in torsion cosmology.

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21

Nikiforova, Vasilisa. "Stability of self-accelerating Universe in modified gravity with dynamical torsion: The case of small background torsion." International Journal of Modern Physics A 33, no. 07 (March 8, 2018): 1850039. http://dx.doi.org/10.1142/s0217751x18500392.

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We consider the model of modified gravity with dynamical torsion. This model was found to have promising stability properties about various backgrounds. The model admits a self-accelerating solution. We have shown previously that if the parameters are adjusted in such a way that the torsion is much greater than the effective cosmological constant, the self-accelerating solution is unstable: there are exponentially growing modes. Here, we study the scalar perturbations in the case when the torsion is of the order of the effective cosmological constant. We find that there are no exponential instabilities.

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22

Nataraj, C. "On the Interaction of Torsion and Bending in Rotating Shafts." Journal of Applied Mechanics 60, no. 1 (March 1, 1993): 239–41. http://dx.doi.org/10.1115/1.2900762.

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The problem of torsional and transverse deformations of a shaft rotating at a constant speed is considered. The displacements are expressed in a perturbation series in terms of a small parameter. Energy expressions are derived to each order and Hamilton’s principle is applied to obtain the equations of motion and the boundary conditions governing the displacement functions of different orders. It is clearly shown that the interaction of torsion and transverse vibration occurs at second order. Previous work reporting results of torsional vibration caused at a frequency equal to twice the rotational speed due to this interaction is confirmed.

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23

Calini, Annalisa M., and Thomas A. Ivey. "Topology and sine-Gordon evolution of constant torsion curves." Physics Letters A 254, no. 3-4 (April 1999): 170–78. http://dx.doi.org/10.1016/s0375-9601(99)00110-3.

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24

Gundlach, J. H. "A rotating torsion balance experiment to measure Newton's constant." Measurement Science and Technology 10, no. 6 (January 1, 1999): 454–59. http://dx.doi.org/10.1088/0957-0233/10/6/307.

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25

Dzhunushaliev, Vladimir. "Cosmological constant and Euclidean space from nonperturbative quantum torsion." International Journal of Geometric Methods in Modern Physics 12, no. 01 (December 28, 2014): 1550008. http://dx.doi.org/10.1142/s0219887815500085.

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Heisenberg's nonperturbative quantization technique is applied to the nonperturbative quantization of gravity. An infinite set of equations for all Green's functions is obtained. An approximation is considered where: (a) the metric remains as a classical field; (b) the affine connection can be decomposed into classical and quantum parts; (c) the classical part of the affine connection is the Christoffel symbols; (d) the quantum part is the torsion. Using a scalar and vector fields approximation it is shown that nonperturbative quantum effects give rise to a cosmological constant and an Euclidean solution.

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26

Pidzhakova, L. M. "Three-webs with covariantly constant curvature and torsion tensors." Journal of Mathematical Sciences 174, no. 6 (April 13, 2011): 653–62. http://dx.doi.org/10.1007/s10958-011-0323-9.

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27

Pidzhakova, L. M. "Three-webs with covariantly constant curvature and torsion tensors." Journal of Mathematical Sciences 177, no. 4 (August 10, 2011): 597–606. http://dx.doi.org/10.1007/s10958-011-0485-5.

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28

de Sabbata, Venzo, and C. Sivaram. "Torsion, wormholes, and the problem of the Cosmological constant." International Journal of Theoretical Physics 30, no. 2 (February 1991): 123–27. http://dx.doi.org/10.1007/bf00670708.

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29

Karagioz, O. V., and V. P. Izmailov. "Measurement of the gravitational constant with a torsion balance." Measurement Techniques 39, no. 10 (October 1996): 979–87. http://dx.doi.org/10.1007/bf02377461.

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30

Kazaras, Demetre, and Ivan Sterling. "An explicit formula for spherical curves with constant torsion." Pacific Journal of Mathematics 259, no. 2 (October 3, 2012): 361–72. http://dx.doi.org/10.2140/pjm.2012.259.361.

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31

Fabbri, Luca. "Conformal gravity with electrodynamics for fermion fields and their symmetry breaking mechanism." International Journal of Geometric Methods in Modern Physics 11, no. 03 (March 2014): 1450019. http://dx.doi.org/10.1142/s0219887814500194.

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In this paper, we consider an axial torsion to build metric-compatible connections in conformal gravity, with gauge potentials; the geometric background is filled with Dirac spinors: scalar fields with suitable potentials are added eventually. The system of field equations is worked out to have torsional effects converted into spinorial self-interactions: the massless spinors display self-interactions of a specific form that gives them the features they have in the non-conformal theory but with the additional character of renormalizability, and the mechanisms of generation of mass and cosmological constants become dynamical. As a final step we will address the cosmological constant problem and the coincidence issue.

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32

Diken, H., and I. G. Tadjbakhsh. "Unbalance Response of Flexible Rotors Coupled With Torsion." Journal of Vibration and Acoustics 111, no. 2 (April 1, 1989): 179–86. http://dx.doi.org/10.1115/1.3269839.

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The effect of coupling with torsion on the unbalance response of flexible rotors, supported by isotropic flexible and damped bearings is investigated. Flexural vibrations of the shaft-disk system are coupled with torsional oscillations through mass eccentricity. The governing equations of motion of the continuous system are solved numerically with a modified Myklestad-Prohl method without the necessity of considering an equivalent lumped system. The cases of constant or harmonic torque applied to the disk are considered. Gyroscopic, rotary inertia, shear deformation, external and internal damping effects are taken into account.

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33

Monterde, J. "Salkowski curves revisited: A family of curves with constant curvature and non-constant torsion." Computer Aided Geometric Design 26, no. 3 (March 2009): 271–78. http://dx.doi.org/10.1016/j.cagd.2008.10.002.

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34

Qiao, Chong, Yanli Zhou, Xiaolin Cai, Weiyang Yu, Bingjie Du, Haiyan Wang, Songyou Wang, and Yu Jia. "Molecular dynamics simulation studies on the plastic behaviors of an iron nanowire under torsion." RSC Advances 6, no. 34 (2016): 28792–800. http://dx.doi.org/10.1039/c6ra06125g.

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35

ROSSI, M., and L. ZANINETTI. "LINEAR AND NONLINEAR EFFECTS ON THE NEWTONIAN GRAVITATIONAL CONSTANT AS DEDUCED FROM THE TORSION BALANCE." International Journal of Modern Physics A 22, no. 29 (November 20, 2007): 5391–400. http://dx.doi.org/10.1142/s0217751x07037329.

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The Newtonian gravitational constant has still 150 parts per million of uncertainty. This paper examines the linear and nonlinear equations governing the rotational dynamics of the torsion gravitational balance. A nonlinear effect modifying the oscillation period of the torsion gravitational balance is carefully explored.

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36

Schaefer, Ted, Salman R. Salman, Timothy A. Wildman, and Glenn H. Penner. "The range of in anisole derivatives. An indicator of torsion and compression of the methoxy group." Canadian Journal of Chemistry 63, no. 3 (March 1, 1985): 782–86. http://dx.doi.org/10.1139/v85-129.

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In a series of anisole derivatives, [Formula: see text], the spin–spin coupling constant between the methyl protons and the ring proton in the ortho position, ranges from −0.23 to −0.38 Hz when the methyl group lies cis to the ortho C—H bond. 5J, as a proximate coupling, is sensitive to the average distance between the coupled protons. Its variation with substituent can be rationalized in terms of torsion about the Csp2—O bond and changes in the bond angles near the methoxy moiety. The theoretical 5J numbers can be empirically reproduced by a cos4 ψ function, where ψ is the angle by which the methoxy group twists out of the benzene plane. In general, large ortho substituents cause an increase in the magnitude of 5J (bond angle changes), strong π electron donors in the para position cause a decrease in the magnitude of 5J (increased torsional freedom), and π electron acceptors do the opposite (decreased torsions).

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37

Olteanu, Anda. "Normally Torsion-free Lexsegment Ideals." Algebra Colloquium 22, no. 01 (January 7, 2015): 23–34. http://dx.doi.org/10.1142/s1005386715000048.

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In this paper we characterize all the lexsegment ideals which are normally torsion-free. This will provide a large class of normally torsion-free monomial ideals which are not square-free. Our characterization is given in terms of the ends of the lexsegment. We also prove that, for lexsegment ideals, the property being normally torsion-free is equivalent to the property of the depth function being constant.

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38

Якушевич, Л. В., and L. V. Yakushevich. "On the DNA Kink Motion Under the Action of Constant Torque." Mathematical Biology and Bioinformatics 11, no. 1 (April 18, 2016): 81–90. http://dx.doi.org/10.17537/2016.11.81.

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The influence of the torsion moment on the DNA kink motion is studied by the methods of mathematical modeling. Time dependence of the kink coordinate, velocity, size, and energy on the different values of the parameters of the external torsion moment have been found. It has been shown that by changing the parameters, by switching on and off of the external action, one could regulate the velocity and the direction of the kink movement. Estimation of the torque value necessary for the kink (open state) movement with the velocity comparable to the transcription velocity, has been made.

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39

Cohen, R., and I. Porat. "Coupled Torsional and Transverse Vibration of Unbalanced Rotor." Journal of Applied Mechanics 52, no. 3 (September 1, 1985): 701–5. http://dx.doi.org/10.1115/1.3169125.

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A model of an unbalanced rotor, driven by a torsion-flexible shaft through a constant velocity joint, is used to investigate the combination-resonance effect in coupled torsional-transverse vibration. Analysis of the nonlinear equations of motion by an asymptotic method yields the instability zones of the system. Results are in very good agreement with those obtained by direct numerical solution of the equations of motion.

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40

Brice, Richard, and Richard Pickings. "Saint-Venant torsion constant of modern precast concrete bridge girders." PCI Journal 66, no. 3 (2021): 23–31. http://dx.doi.org/10.15554/pcij66.3-01.

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Many bridge owners have developed new precast, prestressed concrete bridge girder sections that are optimized for high-performance concrete and pretensioning strands with diameters greater than 0.5 in. (12.7 mm). Girder sections have been developed for increased span capacities, while others fill a need in shorter span ranges. Accurate geometric properties are essential for design. Common properties, including cross-sectional area, location of centroid, and major axis moment of inertia, are generally easy to compute and are readily available in standard design references. Computation of the torsion constant is a different matter. This paper presents the methods and results of a study to determine the torsion constant for many of the modern precast, prestressed concrete bridge girders used in the United States and compares the results with values from the approximate methods of the AASHTO LRFD specifications.

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41

Sapountzakis, Evangelos J. "Bars under Torsional Loading: A Generalized Beam Theory Approach." ISRN Civil Engineering 2013 (March 21, 2013): 1–39. http://dx.doi.org/10.1155/2013/916581.

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In this paper both the static and dynamic analyses of the geometrically linear or nonlinear, elastic or elastoplastic nonuniform torsion problems of bars of constant or variable arbitrary cross section are presented together with the corresponding research efforts and the conclusions drawn from examined cases with great practical interest. In the presented analyses, the bar is subjected to arbitrarily distributed or concentrated twisting and warping moments along its length, while its edges are supported by the most general torsional boundary conditions. For the dynamic problems, a distributed mass model system is employed taking into account the warping inertia. The analysis of the aforementioned problems is complete by presenting the evaluation of the torsion and warping constants of the bar, its displacement field, its stress resultants together with the torsional shear stresses and the warping normal and shear stresses at any internal point of the bar. Moreover, the construction of the stiffness matrix and the corresponding nodal load vector of a bar of arbitrary cross section taking into account warping effects are presented for the development of a beam element for static and dynamic analyses. Having in mind the disadvantages of the 3D FEM solutions, the importance of the presented beamlike analyses becomes more evident.

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42

Dong, Sheng-Jing, Paul S. Hees, Wen-Mei Huang, Sam A. Buffer, James L. Weiss, and Edward P. Shapiro. "Independent effects of preload, afterload, and contractility on left ventricular torsion." American Journal of Physiology-Heart and Circulatory Physiology 277, no. 3 (September 1, 1999): H1053—H1060. http://dx.doi.org/10.1152/ajpheart.1999.277.3.h1053.

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Shortening of oblique left ventricular (LV) fibers results in torsion. A unique relationship between volume and torsion is therefore expected, and the effects of load and contractility on torsion should be predictable. However, volume-independent behavior of torsion has been observed, and the effects of load on this deformation remain controversial. We used magnetic resonance imaging (MRI) with tagging to study the relationships between load and contractility, and torsion. In ten isolated, blood-perfused canine hearts, ejection was controlled by a servopump: end-diastolic volume (EDV) was controlled by manipulating preload parameters and end-systolic volume (ESV) by manipulating afterload using a three-element windkessel model. MRI was obtained at baseline, two levels of preload alteration, two levels of afterload alteration, and dobutamine infusion. An increase in EDV resulted in an increase in torsion at constant ESV (preload effect), whereas an increase in ESV resulted in a decrease in torsion at constant EDV (afterload effect). Dobutamine infusion increased torsion in association with an increase in LV peak-systolic pressure (PSP), even at identical EDV and ESV. Multiple regression showed correlation of torsion with preload (EDV), afterload (ESV), and contractility (PSP; r = 0.67). Furthermore, there was a close linear relationship between torsion and stroke volume (SV) and ejection fraction (EF) during load alteration, but torsion during dobutamine infusion was greater than expected for the extent of ejection. Preload and afterload influence torsion through their effects on SV and EF, and there is an additional direct inotropic effect on torsion that is independent of changes in volume but rather is force dependent. There is therefore potential for the torsion-volume relation to provide a load-independent measure of contractility that could be measured noninvasively.

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43

Chakrabarti, Debraj, Rahul Sahay, and Jared Williams. "Curves of constant curvature and torsion in the 3-sphere." Involve, a Journal of Mathematics 12, no. 2 (January 1, 2019): 235–55. http://dx.doi.org/10.2140/involve.2019.12.235.

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44

Aminov, Yu A. "Surfaces in E4 with a Gaussian torsion of constant sign." Journal of Soviet Mathematics 54, no. 1 (March 1991): 667–75. http://dx.doi.org/10.1007/bf01097409.

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45

Batakis, N. A., K. Farakos, D. Kapetanakis, G. Koutsoumbas, and G. Zoupanos. "Compactification over coset spaces with torsion and vanishing cosmological constant." Physics Letters B 220, no. 4 (April 1989): 513–19. http://dx.doi.org/10.1016/0370-2693(89)90778-8.

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Ahmed, Mohammed Z., and Frank E. Weisgerber. "Torsion constant for matrix analysis of structures including warping effect." International Journal of Solids and Structures 33, no. 3 (January 1996): 361–74. http://dx.doi.org/10.1016/0020-7683(95)00045-c.

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CHO, Y. M., D. G. PAK, and B. S. PARK. "A MINIMAL MODEL OF LORENTZ GAUGE GRAVITY WITH DYNAMICAL TORSION." International Journal of Modern Physics A 25, no. 14 (June 10, 2010): 2867–82. http://dx.doi.org/10.1142/s0217751x10048524.

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Abstract:

A new Lorentz gauge gravity model with R2-type Lagrangian is proposed. In the absence of classical torsion, the model admits a topological phase with an arbitrary metric. We analyze the equations of motion in constant curvature space–time background using the Lagrange formalism and demonstrate that the model possesses a minimal set of dynamic degrees of freedom for the torsion. Surprisingly, the number of torsion dynamic degrees of freedom equals the number of physical degrees of freedom for the metric tensor. An interesting feature of the model is that the spin-2 mode of torsion becomes dynamical essentially due to the nonlinear structure of the theory. We perform covariant one-loop quantization of the model for a special case of constant curvature space–time background. We treat the contortion as a quantum field variable whereas the metric tensor is kept as a classical object. We discuss a possible mechanism of an emergent Einstein gravity as a part of the effective theory induced due to quantum dynamics of torsion.

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Bai, Cheng, and Jin Huang. "Modeling and Active Control of Circular Electrostatic Torsional Micromirror." Advanced Materials Research 629 (December 2012): 649–54. http://dx.doi.org/10.4028/www.scientific.net/amr.629.649.

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Three main obstacles in modeling electrostatic torsional micromirror are hard to calculate – damping coefficient, mechanical spring constant and electrostatic torsion accurately. Because that parameter variations and model uncertainty of the torsional micromirror resulting from fabrication imperfections are inevitable, it is another problem to seek a control scheme for achieving accurate positioning and trajectory tracking of an electrostatic torsional micromirror. In this paper, aimed at a real prototype of circular electrostatic torsional micromirrorr, both static and dynamic behaviors are modeled and studied. A novel nonlinear Proportional, Integral and Derivative (PID) control are proposed in succession. Simulation results show that the system model derived is more accurate to the micromirror and the nonlinear PID can eliminate the static deviation.

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HOUNDJO, M. J. S., D. MOMENI, and R. MYRZAKULOV. "CYLINDRICAL SOLUTIONS IN MODIFIED f(T) GRAVITY." International Journal of Modern Physics D 21, no. 14 (December 2012): 1250093. http://dx.doi.org/10.1142/s0218271812500939.

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We investigate static cylindrically symmetric vacuum solutions in Weyl coordinates in the framework of f(T) theory of gravity, where T is the torsion scalar. The set of modified Einstein equations is presented and the forthcoming equations are established. Specific physical expressions are assumed for the algebraic function f(T) and solutions are obtained. Moreover, general solution is obtained with finite values of u(r) on the axis r = 0 and this leads to a constant torsion scalar. Cosmological constant is also introduced and its relation to Linet–Tian solution in GR is commented.

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Wang, Xiao-Wei, De-Guang Shang, and Yu-Juan Sun. "A weight function method for multiaxial low-cycle fatigue life prediction under variable amplitude loading." Journal of Strain Analysis for Engineering Design 53, no. 4 (March 27, 2018): 197–209. http://dx.doi.org/10.1177/0309324718763671.

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A weight function method based on strain parameters is proposed to determine the critical plane in low-cycle fatigue region under both constant and variable amplitude tension–torsion loadings. The critical plane is defined by the weighted mean maximum absolute shear strain plane. Combined with the critical plane determined by the proposed method, strain-based fatigue life prediction models and Wang-Brown’s multiaxial cycle counting method are employed to predict the fatigue life. The experimental critical plane orientation and fatigue life data under constant and variable amplitude tension–torsion loadings are used to verify the proposed method. The results show that the proposed method is appropriate to determine the critical plane under both constant and variable amplitude loadings.

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