scholarly journals Rigid body rotation of the left ventricle in hidradenitis suppurativa (a case from the three-dimensional speckle-tracking echocardiographic MAGYAR-Path Study)

2018 ◽  
Vol 8 (5) ◽  
pp. 547-550
Author(s):  
Attila Nemes ◽  
Réka Kovács ◽  
Árpád Kormányos ◽  
Győző Szolnoky ◽  
Anita Kalapos ◽  
...  
Keyword(s):  
Left Ventricle ◽  
Rigid Body ◽  
Speckle Tracking ◽  
Hidradenitis Suppurativa ◽  
Three Dimensional ◽  
Body Rotation ◽  
Rigid Body Rotation

scholarly journals Controlling Mixing Inside a Droplet by Time Dependent Rigid-Body Rotation

2008 ◽  
Author(s):  
Rodolphe Chabreyrie ◽  
Dmitri Vainchtein ◽  
Cristel Chandre ◽  
Pushpendra Singh ◽  
Nadine Aubry
Keyword(s):  
Rigid Body ◽  
Liquid Droplet ◽  
Three Dimensional ◽  
Time Dependent ◽  
Mixing Enhancement ◽  
Body Rotation ◽  
Rigid Body Rotation ◽  
Digital Microfluidic ◽  
And Control ◽  
Time Periodic

The use of microscopic discrete fluid volumes (i.e., droplets) as microreactors for digital microfluidic applications often requires mixing enhancement and control within droplets. In this work, we consider a translating spherical liquid droplet to which we impose a time periodic rigid-body rotation which we model using the superposition of a Hill vortex and an unsteady rigid body rotation. This perturbation in the form of a rotation not only creates a three-dimensional chaotic mixing region, which operates through the stretching and folding of material lines, but also offers the possibility of controlling both the size and the location of the mixing. Such a control is achieved by judiciously adjusting the three parameters that characterize the rotation, i.e., the rotation amplitude, frequency and orientation of the rotation. As the size of the mixing region is increased, complete mixing within the drop is obtained.

scholarly journals “Rigid body rotation” of the left ventricle in hypoplastic right-heart syndrome: a case from the three-dimensional speckle-tracking echocardiographic MAGYAR-Path Study

2014 ◽  
Vol 25 (4) ◽  
pp. 768-772 ◽  
Author(s):  
Attila Nemes ◽  
Kálmán Havasi ◽  
Tamás Forster
Keyword(s):  
Rigid Body ◽  
Three Dimensional ◽  
Left Ventricular ◽  
Body Rotation ◽  
Right Heart ◽  
Rigid Body Rotation ◽  
Left Ventricular Twist ◽  
Ventricular Twist ◽  
First Time ◽  
Left Ventricular Base

AbstractLeft ventricular twist results from the movement of two orthogonally oriented muscular bands of the helical myocardial structure, with a consequent clockwise rotation of the left ventricular base and counterclockwise rotation of the left ventricular apex. To the best of the authors’ knowledge, this is the first time that left ventricular “rigid body rotation”, the near absence of left ventricular twist in hypoplastic right-heart syndrome, has been demonstrated.

Diagnostic Value of Rigid Body Rotation in Noncompaction Cardiomyopathy

2011 ◽  
Vol 24 (5) ◽  
pp. 548-555 ◽  
Author(s):  
Bas M. van Dalen ◽  
Kadir Caliskan ◽  
Osama I.I. Soliman ◽  
Floris Kauer ◽  
Heleen B. van der Zwaan ◽  
...  
Keyword(s):  
Rigid Body ◽  
Diagnostic Value ◽  
Body Rotation ◽  
Rigid Body Rotation ◽  
Noncompaction Cardiomyopathy

Reduction of residual vibrations in a rotating flexible beam with a moving payload mass

1997 ◽  
Vol 211 (1) ◽  
pp. 25-34 ◽  
Author(s):  
S Choura
Keyword(s):  
Rigid Body ◽  
Position Control ◽  
Rate Of Change ◽  
Torque Control ◽  
Flexible Beam ◽  
Control Force ◽  
Axial Motion ◽  
Body Rotation ◽  
Rigid Body Rotation ◽  
Payload Mass

The reduction of residual vibrations for the position control of a flexible rotating beam carrying a payload mass is investigated. The common practice used to find the position control of a flexible multi-link arm is to assign a torque actuator to each joint while the payload mass is kept fixed relative to the end-link during the time of manoeuvre. This paper examines the stability of the system if either the payload is freed accidentally to move along the beam during the time of manoeuvre or is allowed to span the beam in a desired path for control purposes. A candidate Lyapunov function is constructed and its time rate of change is examined. It is shown that the use of a PD (proportional plus derivative) torque control yields a convergence of residual vibration to zero, an attainment of the rigid-body rotation to a prespecified desired angle of manoeuvre and a constant velocity of the payload mass as it moves relative to the beam. For manipulation purposes, an additional control force is added to the moving actuator in order to regulate its axial motion. It is shown that allowing the axial motion of the payload mass in a prescribed manner leads to a considerable reduction of its residual vibrations as compared to the case where the payload mass is fixed to the beam tip during the time of manoeuvre. Stability is also verified through simulations of rigid-body rotation and payload axial motion track prespecified reference trajectories.

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