The sound properties along a long rectangular enclosure with a circular source on the top wall and rectangular opening at the side wall are studied. A mathematical model of average pressure at an opening contributed by the sound source and assuming air piston at the opening is derived in terms of the acoustic mode for a rigid duct. Three-dimensional numerical modelling is conducted to compare t...

In the present research, behavior of SPSPs with two rectangular openings and effect of strengthening different subpanels with various stiffener arrangements is investigated. In the next step, to investigate the effect of changing opening width on the trend of degradation shear stiffness and strength of the panel, the opening width is changed. In the third step, to study the effect of changing o...

A simple approach for the beam size mesurements with optical diffraction radiation from a slit target is presented. The estimations show that it is possible to measure the beam size with a resolution of about ~1μm. We developed a new approach for calculating diffraction radiation characteristics from a rectangular finite size target with a rectangular opening in it to be able to estimate the in...

the effect of steel plate thickness on the repair effectiveness of rc beam is presented in this paper. a total of four beams were tested, one beam repaired by cfrp with a thickness of 1.2 mm and used as a control beam, and three beams repaired by a steel plate. steel plates with a thickness of 2 mm, 3 mm, and 4 mm were used in repairing the beams. the maximum load-carrying capacity, deflection ...

We prove the absence of non-scattering energies for potentials in the plane having a corner of angle smaller than π. This extends the earlier result of Bl̊asten, Päivärinta and Sylvester who considered rectangular corners. In three dimensions, we prove a similar result for any potential with a circular conic corner whose opening angle is outside a countable subset of (0, π).