The azimuthal, far field directivity of a scale fan model was measured in high resolution. The model is a 12 inch diameter rotor with 16 blades followed by 40 stator vanes. The tests were conducted at the nominal 100% speed corresponding to a tip speed of 905 ft/sec. Measurement of the radiated sound field, forward of the fan, was made in an anechoic chamber with an inflow control device and a ...

Speech and singing directivity in the horizontal plane was examined using simultaneous multi-channel full-bandwidth recordings to investigate directivity of high-frequency energy, in particular. This method allowed not only for accurate analysis of running speech using the long-term average spectrum, but also for examination of directivity of separate transient phonemes. Several vocal productio...

On 8 January 2022, an M S 6.9 earthquake occurred in the Menyuan county, Qinghai province at northeastern margin of Tibetan Plateau. A dense observatory network consisting accelerographs and intensity meters has obtained many acceleration recordings this region, which previously had only a few strong motion recordings. Using data recorded by 141 micro-electro mechanical system (MEMS)-based with...

Abstract An intense laser pulse focused in water could induce plasma expansion, which can be used as an impulsive sound source. The optoacoustic underwater source is very useful marine applications; however, the poor reproductivity and sharp directivity of emitted signals a big problem. acoustic emission by breakdown are measured laboratory experiment this paper, results show that both directio...

Recently, concerning failure of structures due to earthquakes, special investigations of near fault ground motions have been noticed. Hence, in this paper, characteristics of near field ground motions have been considered in horizontal and vertical directions. In this consideration, the record averages have been compared with Uniform Building Code and Eurocode8 spectra in two levels. In additio...

It has been suggested by Morse and Ingard that the sound radiation of a loudspeaker in a box is comparable to that of a spherical cap on a rigid sphere. This has been established recently by the present authors, who developed a computation scheme for the forward and inverse calculation of the pressure due to a harmonically excited, flexible cap on a rigid sphere with an axially symmetric veloci...

In this paper a simple model of a three story building with inclined first-story columns has presented. The stories are supposed to be rigid and are connected to axially rigid mass less columns by elasto-plastic rotational springs and linear rotational dampers. The considered model is subjected to horizontal component of fault normal pulse with different magnitudes and the governed nonlinear di...

Aortic stiffness determines the glomerular filtration rate (GFR) and predicts the progressive decline of the GFR. However, the underlying pathophysiological mechanism remains obscure. Recent evidence has shown a close link between aortic stiffness and the bidirectional (systolic forward and early diastolic reverse) flow characteristics. We hypothesized that the aortic stiffening-induced renal d...