An efficient design analysis method for cantilevered beam-type piezoelectric energy harvesters was developed for the
prediction of the electric power output, based on the finite element method and the design optimization of piezoelectric
materials. The optimum topology of a piezoelectric material layer could be obtained by a newly developed topology
optimization technique for piezoelectric materials which utilized the electromechanical coupling equations, MMA
(method of moving asymptotes), and SIMP (solid isotropic material with penalization) interpolation. Using the design
optimization tool, several cantilevered beam-type piezoelectric energy harvesters which fluctuated in the region of vortex
shedding were developed, that consisted of two different material layers - piezoelectric and aluminum layers. In order to
obtain maximum electric power, the exciting frequency of the cantilevered energy device must be tuned as close to the
natural frequency of the beam as possible. Using the method, the effects of geometric parameters and several
piezoelectric materials (PZT, PVDF, and PZT fiber composites) attached to the beam device on power generation were
investigated and the electric characteristics were evaluated. The three kinds of material coefficients such as elasticity,
capacitance, and piezoelectric coupling are interpolated by element density variables. Then, the shape and size design
optimizations for the cantilevered beam geometries with an optimum piezoelectric topology have been performed for a
base model.
This paper introduces a novel adaptive algorithm for target detection in infrared search and track (IRST) system. The
algorithm is proposed on the basis of robust and adaptive method that is invariant to the prior uncertainty with respect to
statistical properties of cluttered background and noise. The essence of proposed algorithm is to design the detection
index over two images obtained by processing the given image through the local gamma correction (LGC) and the
estimation of target motion. And the detection index (DI) is obtained by the two factors which calculated relations
between two images: luminance rate (LR), and contrast rate (CR). Results of simulation show that the proposed
algorithm gives an enormous gain on real infrared image sequences.
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