this paper presents a low-cost compact planar microstrip-fed monopole antenna and its four-element array design for ultra-wideband (uwb) wireless communication and target detection applications, respectively, operating in the frequency span of 3 ghz to 11 ghz. a prototype was fabricated and then measured based on optimal parameters. the results of reflection coefficient (s11) and radiation patt...

introductionmany aspect strongly influence regional climate includes localized surface processes, large-scale patterns, especially mid and upper level tropospheric circulation and many factors control precipitation in the west of iran includes location of emigrate westerly winds systems, jet streams location, humidity flux and topography. upper tropospheric jet stream constitutes a significant ...

Quiet time arcs observed from the Greenland all-sky camera network have been ordered in corrected geomagnetic latitude/time mass plots according to the values of the Y and Z components of the IMF. Two different patterns of discrete quiet arcs occur. In one system the arcs are ordered along the statistical auroral oval; in the other, which we have called the polar cap pattern of discrete arcs, t...

Geometric frustration gives rise to new fundamental phenomena and is known to yield the formation of exotic states of matter, such as incommensurate crystals, modulated liquid-crystalline phases, and phases stabilized by defects. In this Letter, we present a detailed study of polar structure of freely suspended fluid filaments in a polarization modulated liquid-crystal phase. We show that a per...

Relevant features in the visual image are often spatially extensive and have complex orientation structure. Our perceptual sensitivity to such spatial form is demonstrated by polar Glass patterns, in which an array of randomly-positioned dot pairs that are each aligned with a particular polar displacement (rotation, for example) yield a salient impression of spatial structure. Such patterns are...

Pattern matching is a widely used technique in functional languages, especially those in the ML and Haskell traditions. Although pattern matching is typically not built into languages in the Lisp tradition, it is often available via libraries built with macros. We present a sophisticated pattern matcher for Racket, which extends the language using macros, supports novel and widelyuseful pattern...

we present observation of polar coronal hole plumes with foot point jets that shows evidence of longitudinal acceleration. the series of event, occurring in the north coronal hole on 10 july 2010, was observed by the aia telescopes of the solar dynamic observatory (sdo mission) in the euv lines, with unprecedented details. the structures along the plume show a propagating outward velocity of ab...