This paper describes a theoretical and experimental investigation into an electrical Helmholtz resonator (EHR): that is, an active noise control (ANC) loudspeaker used in conjunction with a microphone and a feedback ...

We extend classic Sommerfeld and Silver-Muller radiation conditions for bounded scatterers to acoustic and electromagnetic fields propagating over three isotropic homogeneous layers in three dimensions. If x = (x(1), x(2), ...

Neste artigo apresentamos uma descrição geral da física do violino, analisando os conceitos que lhes dão sustentação física e que revelam toda a riqueza e o potencial pedagógico do assunto. Destacamos as contribuições de ...

O estudo do escoamento de jato é relevante devido à sua importância em aplicações industriais, tais como, sistemas de propulsão, troca de calor e massa e estabilização de tiras, placas e blocos durante o tratamento térmico ...

TThis thesis deals with the proposal, analytical background and practical implementation of fiber optic based sensors for measuring electrical variables in high voltage systems. The thesis presents the physical and ...

We report new results from the 50-MHz Jicamarca radar in Peru (12°S, 77°W), which is able to observe backscatter from the daytime mesosphere on any given day. Since 2005, the radar has been operated in a high-power MST-ISR ...

The aquatic vegetation is ubiquitous worldwide, from low temperature areas to tropical shallow coastal zones (Van Der Heide et al., 2007). These ecosystems provide a productive life cyle being the habitat for many marine ...

In his study, Wang proved that the fundamental frequency coefficient of a circular annular membrane fixed at the outer radius ´b´ and at the inner radius ´a´, is the same eigenvalue as in the case of a solid circular ...