We have employed our recently developed Green’s function formalism to study the dielectric behavior of a model membrane, formed by two periodic interfaces separating two media of different dielectric constants. The Maxwell’s equations are converted into a surface integral equation; thus it greatly simplifies the solutions and yields accurate results for membranes of arbitrary shape. The integra...

To date, research on the visual control of locomotion, or optic flow, has been treated largely as a computational problem wherein formal descriptions are sought to character-ise the change in the image pattern on the retina that results from observer translation with concomitant eye rotation (se Lappe et al 1999, for details). Various models have been proposed (see Hildreth and Royden 1998, for...

In August 2009 the Sun illuminated Saturn's rings from almost exactly edge-on, revealing a subtle corrugation that extends across the entire C ring. This corrugation's amplitude is 2 to 20 meters and its wavelength is 30 to 80 kilometers. Radial trends in the corrugation's wavelength indicate that this structure--like a similar corrugation previously identified in the D ring--results from diffe...

dotracheal tube and are composed of inspiratory and expiratory corrugated limbs. The two breathing tubes carry respiratory gases with volatile anesthetics to and from patients during general anesthesia. Although longer corrugated breathing tubes allow the anesthesia machine to be located farther from the patients, they are so long and flexible that they tend to hang down below the operating tab...

Multilayered solid structures made of isotropic, transversely isotropic, or general anisotropic materials are frequently used in aerospace, mechanical, and civil structures. Ultrasonic fields developed in such structures by finite size transducers simulating actual experiments in laboratories or in the field have not been rigorously studied. Several attempts to compute the ultrasonic field insi...

Abstract We performed the first-principles calculation on common thermoelectric semiconductors Bi 2 Te 3 , Se SiGe, and PbTe in bulk three-dimension (3D) two-dimension (2D). found that miniaturisation of materials does not generally increase figure merit ( ZT ) according to Hicks Dresselhaus (HD) theory. For example, values 2D (0.32) SiGe (0.04) are smaller than their 3D counterparts (0.49 0.09...

The classic first-order thrust approximation for solar sails is analytically extended to include the effects of secondary reflections and generalized in a practical Finite Element Model (FEM) based routine. Examination and inclusion of secondary reflection forces are shown to grow increasingly non-trivial as the deformation becomes more extreme. The approach taken herein does not address the “b...

Microstrip antennas are widely used in a broad range of military and commercial applications due to its low cost, low profile, easy fabrication and light weight. But this kind of antenna also has some drawbacks. For example, the diffraction of surface waves at the edge of finite grounded substrate decreases the antenna efficiency and degrades the antenna pattern [1]. In the phased array antenna...