This paper extends the theory of the diffraction of sound on 1D corrugated surfaces to 2D corrugated surfaces. Such surfaces, that are egg crate shaped, diffract incoming sound into all polar directions, which is fundamentally different from 1D corrugated surfaces. A theoretical justification is given for extending the classical grating equation to the case of incident inhomogeneous waves, for ...

An axially corrugated horn antenna with an elliptically shaped taper is proposed for satellite communication applications. This structure is a good candidate for the feed of reflectors and also for improving the electrical properties of reflector antennas. A tapering method is used to justify the horizontal location of the corrugation profile which improves the electrical performance of the pre...

The paper focuses on optimization of lightweight sandwich panels with prismatic cores subject to bending loads in the two principal in-plane directions. Comparisons are made with optimal designs of panels with corrugated cores: a limiting case. When optimized for loading transverse to the prism axis, prismatic panels outperform those with corrugated cores, especially at lower loads. In contrast...

In this work, an analytical study on the bending stiffnesses of corrugated board has been performed. Formulations to calculate the bending stiffnesses D11, D22, D12, and D66 of the equivalent plate representing the corrugated board have been established, and then compared to expressions suggested by other investigators. Several methods for modeling the shape of the corrugated orthotropic medium...

A problem of reflection and transmission of a plane shear wave incident at a corrugated interface between transversely isotropic inhomogeneous and visco-elastic half-spaces is investigated. Applying appropriate boundary conditions and using Rayleigh’s method of approximation expressions for reflection and transmission coefficients are obtained for the first and second order approximation of the...

A 74-year-old male patient consulted us for an elastic firm mass in the right buccal mucosa. CT examination revealed a well-circumscribed oval cystic lesion in the anterior region of the masseter muscle. On MRI, the lesion showed a low signal on T1-weighted image and a high signal on T2-weighted image. Aspiration biopsy demonstrated the presence of squamous cells in whitish liquid. Under the di...

abstract one of the most frequently encountered cases of rapid varied flow is the hydraulic jump. it occurs when a supercritical open channel flow changes into sub critical flow. in the present research, the experimental study of the hydraulic jump on seven sinusoidal corrugated beds with different wave steepness. the wave steepness of sinusoidal corrugated beds is in the range of 0.1667 to 0.7...

an aircraft wing needs to display different mechanical behavior in different directions. 1- stiffness in the spanwise (transverse to the corrugation) direction which enables the aerodynamic and inertial loads to be carried. 2- compliance in the chordwise (corrugation) direction which would allow shape changes and increases in surface area; whereas a corrugated sheet due to their special geometr...