Filter design specifications can be manifest in all manner of necessity, whether they are high-pass, low-pass, band-pass, or stop-band filters. In addition, the parameters for such filters are defined for a very specific application. A design for a lowpass filter with a pass-band of 2k Hz and a stop-band of 4k will be discussed. The further properties of the filter are to allow for a 48 dB drop...

Low-threshold lasing is observed at the edge of the stop band of a one-dimensional structure-a dye-doped cholesteric liquid-crystal film. The mode closest to the edge has the lowest lasing threshold. The rates of spontaneous and stimulated emission are suppressed within the stop band and enhanced at the band edge. The ratio of right to left circularly polarized spontaneous emission is in good a...

As part of an indoor mutt/path measurement system, discone antennas featuring simple N~onnector feed systems have bHn designed for the 1.0 to 2.0 GHz band. Extensive experimentation reveals that excellent performance (VSWR < 15:1 across the band) can be obtained with a simple "snap-on" feed/mount method, and that VSWR is most sensitive to the diameter of the disc feed conductor. Per· formance d...

Periodic piezoelectric beams have been used for broadband vibration energy harvesting in recent years. In this paper, a periodic folded piezoelectric beam (PFPB) is introduced. The PFPB has special features that distinguish it from other periodic piezoelectric beams. The Adomian decomposition method (ADM) is used to calculate the first two band gaps andtwelve natural frequencies of the PF...

Inappropriate response tendencies may be stopped via a specific fronto/basal ganglia/primary motor cortical network. We sought to characterize the functional role of two regions in this putative stopping network, the right inferior frontal gyrus (IFG) and the primary motor cortex (M1), using electocorticography from subdural electrodes in four patients while they performed a stop-signal task. O...

This paper presents a new concept to implement a tunable filter metamaterial with dual negative refraction composed of ferrite slabs and metallic resonators, including split-ring resonators (SRR), and short wire pairs. The ferrite slabs under an applied magnetics bias provide one magnetic resonance frequency band and the metallic resonators provide another one. The continuous wires within the m...

An eigenvalue-eigenvector approach for the design of two-channel linear phase quadrature mirror filter (QMF) bank is proposed. To reduce the computational complexity, finite-duration impulse response (FIR) low-pass prototype filter of the filter bank is represented by polyphase components. The design problem is formulated to optimize the filter tap weights of the low-pass prototype filter of th...