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...

objective the purpose of this study was to assess the frequency of complications of endotracheal intubation (eti) in neonates. methods the newborns that were admitted and needed urgent or semi-urgent intubation were enrolled in this study over a 1 year period. route for intubation in all cases were orotracheal. cases were not routinely sedated or paralyzed. the patients were clinically and radi...

background and purpose: inserting a nasogastric tube, though a common clinical procedure with widespread use for critically ill patients, can produce unexpected complications so that tube misplacement into the lungs is a potential complication with serious consequences. the reliability of common bedside methods to differentiate between pulmonary and gastric placement has not been acceptable. th...

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...

Response surface methodology (RSM) is a statistical method useful in the modeling and analysis of problems in which the response variable receives the influence of several independent variables, in order to determine which are the conditions under which should operate these variables to optimize a corrugated box production process. The purpose of this research is to create response surface mode...

In the present article, a numerical study is performed to investigate the crushing behavior of cylindrical and conical corrugated composite tubes. Different aluminum foams are applied to the proposed structures in order to offer an excellent energy absorption capacity. The crushing behavior of tubes are evaluated in terms of two parameters: SEA (specific energy absorption) and CFE (crush force ...