Thin structured rigid body for acoustic absorption

Theoretical requirements for broadband perfect absorption of acoustic waves by ultra-thin elastic meta-films

We derive and numerically demonstrate that perfect absorption of elastic waves can be achieved in two types of ultra-thin elastic meta-films: one requires a large value of almost pure imaginary effective mass density and a free space boundary, while the other requires a small value of almost pure imaginary effective modulus and a hard wall boundary. When the pure imaginary density or modulus ex...

the efficacy of rigid bronchoscopy for foreign body aspiration

the aim of the current study was to determine the pattern, presentation and management of foreign body aspiration in our  population.  this prospective study comprised 55 patients with foreign body aspiration admitted to our department from january 2009 to december 2011. all patients underwent rigid bronchoscopy under local or general anesthesia. the patients’ demographic information along with...

Title : Rigid body dynamics

2 Rigid - Body Kinematics

Gregory S. Chirikjian Johns Hopkins University 2.1 Rotations in Three Dimensions Rules for Composing Rotations • Euler Angles • The Matrix Exponential 2.2 Full Rigid-Body Motion Composition of Motions • Screw Motions 2.3 Homogeneous Transforms and the Denavit-Hartenberg Parameters Homogeneous Transformation Matrices • The Denavit-Hartenberg Parameters in Robotics 2.4 Infinitesimal Motions and A...

RNG Rigid Body Motion

This note outlines how the coupling between the motion of rigid bodies immersed in a fluid and the motion of this fluid is handled in XNS. For a rigid body one has a group of nodes which define the surface of the rigid body called “reference node group” (RNG). For each RNG we save the properties of motion in arrays which in the following we will call “RNG arrays”. They contain the bottom and to...