We study the scattering of an incident wave by a composite medium with periodic microstructure in a slab geometry. We compute the expansion on the wave field in powers of the parameter = d/λ, where d is the characteristic scale of the microstructure and λ is the wavelength. For ε = 0 this corresponds to homogenization theory. Here, we focus on the correction terms for ε > 0 and compute the freq...

In this study, a sandwich beam with periodic multiple dissipative resonators in the sandwich core material is investigated for broadband wave mitigation and/or absorption. An analytical approach based on the transfer matrix method and Bloch theorem is developed for both infinite and finite sandwich structures. Wave attenuation constants are theoretically obtained to examine the effects of vario...

BACKGROUND Elevated blood pressure is the leading modifiable risk factor for cardiovascular disease (CVD) and premature death. The blood pressure waveform consists of discrete hemodynamic components, derived from measured central pressure and flow, which may contribute separately to risk for an adverse outcome. However, pressure-flow measures have not been studied in a large, community-based sa...

acetylation is a chemical modification of wood to enhance its properties. ir-spectroscopy is a useful technique for proofing chemical bondings in wood and the at-tenuated total reflection (atr) infrared spectroscopy technique was applied as an eas-ier technique over other ir-spectroscopies. in this research, different degrees of acetyla-tion, weight percentage gains (wpgs) in beech and pine min...

By means of the Kedem-Katchalsky thermodynamic description of active transport, a relationship has been derived between the apparent reflection coefficient and the Staverman reflection coefficient for passive transport of a solute which is both actively and passively transported. The relationship between volumetric flow and its driving forces, containing the Staverman reflection coefficient, wa...

An estimate is derived for the error committed by the introduction of artificial boundaries and corresponding artificial boundary conditions when solving wave equations on unbounded domains. The estimate has two terms. One is proportional to the largest reflection coefficient for the artificial boundary condition, the maximum taken only on those rays which appear in the computation. The second ...

A full-wave moment-method technique developed for the analysis of quasi-optical (QO) systems is used to model finite grid structures in a lens system. This technique incorporates an electric-field dyadic Green’s function for a grid centered between two lenses. This is derived by separately considering paraxial and nonparaxial fields. Results for the driving point reflection coefficient of a 3 3...

In a previous Letter [Tsang and Psaltis, Opt. Lett.31, 2741 (2006)], we assert that the total reflection coefficient of two dielectric slabs goes to zero in the limit of single-waveguide resonance. A more careful derivation shows that this is not the case. The correct condition in which reflectionless evanescent-wave amplification can be achieved by two dielectric planar waveguides is derived i...

Microstrip patch antenna is a flat shape, light weight and low cost antenna that used to receive and transmit electromagnetic wave. This paper describes the design and development of a microstrip patch antenna for salinity and sugar detection. The microstrip antenna was designed and fabricated using Computer Simulation Technology (CST) Microwave Studio and Taconic TLY-5 substrate, respectively....