Recently, compressive sampling has received significant attention as an emerging technique for rapid volumetric imaging. We have previously investigated volumetric optical coherence tomography (OCT) image acquisition using compressive sampling techniques and showed that it was possible to recover image volumes from a subset of sampled images. Our previous findings used the multidimensional wavelet transform as the domain of sparsification for recovering OCT image volumes. In this report, we analyzed and compared the potential and efficiency of three other image transforms to reconstruct the same volumetric OCT image. Two quantitative measures, the mean square error and the structural similarity index, were applied to compare the quality of the reconstructed volumetric images. We observed that fast Fourier transformation and wavelet both are capable of reconstructing OCT image volumes for the orthogonal sparse sampling masks used in this report, but with different merits.

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A novel micromachined accelerometer without proof mass, based on the buoyancy of a heated fluid around a polysilicon heater, has previously been developed and reported. Significant features of this class of accelerometer include low cost and the combination of high sensitivity with high survivability. However, one of its big disadvantages is thermal drift: the sensitivity changes rapidly as the ambient temperature changes. A recent numerical and experimental study has shown that the sensitivity of the convective accelerometer is a function of the Rayleigh number of the working fluid. Using this criterion, a few liquids were selected as potential working fluids to improve the sensitivity of the accelerometer. The CFD program ‘FLOTRAN’ was used to model accelerometer performance using each of these fluids. Based on FLOTRAN modeling, some fluids were selected for experimental investigation. The thermal drift of the accelerometer using different working fluids was documented and the reasons for this thermal drift were discovered. Based on this observation, some possible solutions were proposed to reduce or eliminate the thermal drift.

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