After David’s pioneering contribution, many authors have claimed that the prevalence of the QWERTY keyboard layout is an instance of lock-in on an inferior technology, because the Dvorak Simplified Keyboard is more efficient. But other authors, notably Liebowitz and Margolis, have disputed this claim. Here we proceed to examine the relative efficiency of the two layouts by computational means. ...

The perfectly matched layer (PML) was first introduced by Berenger as a material absorbing boundary condition (ABC) for electromagnetic waves. In this paper, a method is developed to extend the perfectly matched layer to simulating seismic wave propagation in poroelastic media. This nonphysical material is used at the computational edge of a finite-difference algorithm as an ABC to truncate unb...

This paper studies dynamic stability of homogeneous beams with piezoelectric layers subjected to periodic axial compressive load that is simply supported at both ends lies on a continuous elastic foundation. The displacement field of beam is assumed based on Bernoulli-Euler beam theory. Applying the Hamilton's principle, the governing dynamic equation is established. The influences of applied v...

The Casimir force between parallel plates of arbitrary kind is shown to be simply related to the plates transmission and reflection coefficient. A trivial application of this general relation leads to known Lifshitz force between dielectrics as well as its generalizations. The simple two ideally conducting parallel plates Casimir force F = − π 240 h̄c a4 [1] recently been measured experimentally...

This paper presents a two-probe implementation of microwave interferometry for displacement measurement at an unknown reflection coefficient. Theoretically, the proposed technique gives the exact value of the displacement for reflection coefficients (at the location of the probes) no greater than 1/ √ 2 and in the general case determines it to a worst-case accuracy of about 4.4% of the operatin...

As an important operator in polygon cluster generalization, the displacement has two contributions. One is to resolve the proximity conflicts to guarantee the legibility constraint. Another is to act as the prior operator of other generalization operator, such as aggregation. This paper presents a field based method to deal with the displacement of polygon cluster in both aspects above. On the ...

The vibration performance is critical to the suspension control and torque precision of magnetically suspended momentum flywheel (MSMW). translational torsional MSMW are investigated in this article, damping regulation method proposed improve anti-vibration MSMW. Firstly, modellings MSMW, including dynamic models displacement coordinate, developed, comprehensive characteristics investigated. Mo...