This work concerns an extension of usual radar imaging in which the pictures of the target do not simply exhibit the position of elementary reflectors but also give the behavior of these reflectors when the frequency and the direction of illumination vary. Essentially, the technique consists in describing the target by a generalized image which can be computed from the knowledge of the backscat...

The approximation functions of the directivity of the light emitting diodes (LED) have been investigated. LEDs used in large scale LED video displays have been studied. LED directional properties among the other parameters define the video display image quality. The simplicity of an approximation function and ease of analytical handling have been targeted. These functions suppose to be used in ...

[1] We measure direction and amplitude of ocean-generated continuous seismic noise in the western United States. Slowness direction of the noise is determined using array beamforming, and particle motion direction from individual three-component stations. We find two surprising results. First, the noise is highly monodirectional at all sites, regardless of coastal distance. A single narrow gene...

A simple and compact high gain Dielectric Resonator Antenna (DRA) for Ku band frequency operation is proposed in this paper. Ku band is a microwave band having frequency range 12 to 18 GHz. Proposed DRA is based on the principal of the dual resonance and defected ground structure (DGS) having rectangular slot. DRA design resonates at frequency 15.2 GHz and 18 GHz in Ku band frequency operation....

at , with a directivity value of 3.32, and the higher local maximum is located at , with a directivity of 3.26. Another significant local maximum results at ( , 1.09), of directivity 3.10. Thus, this problem represents a typical case of two-dimensional (2-D) unimodal optimization function with a strong local maximum and, moreover, accomplishes all the additional features, mentioned above, that ...

The objective of the study presented herein is to access the influence of rupture directivity on the inducement of liquefaction in loose, saturated sand. Rupture directivity is a near fault phenomenon that results in a pronounced double-sided velocity pulse in the strike normal component(s) of motion. Using the Palmgren-Miner fatigue theory, implemented for low cycle fatigue conditions, the num...