In this article, an alternative indoor positioning mechanism is proposed considering finite memory structure filter as well as measurement delay. First, a finite memory structure filter with a measurement delay is designed for the indoor positioning mechanism under a weighted least-squares criterion, which utilizes only finite measurements on the most recent window. The proposed finite memory structure filtering-based mechanism gives the filtered estimates for position, velocity, and acceleration of moving target in real time, while removing undesired noisy effects and preserving desired moving positions. Second, the proposed mechanism is shown to have good inherent properties such as unbiasedness, efficiency, time-invariance, deadbeat, and robustness due to the finite memory structure. Third, through discussions about the choice of window length, it is shown that this can be considered as a useful design parameter to make the performance of the proposed mechanism as good as possible. Finally, computer simulations show that the performance of the proposed finite memory structure filtering-based mechanism can outperform the existing infinite memory structure filtering-based mechanism for the abruptly varying acceleration of moving target. KeywordsIndoor positioning system, wireless sensor networks, measurement delay, finite memory structure filter, infinite memory structure filter.

An in vitro enzyme assay using radioisotope-labeled (3) H-castasterone ((3) H-CS) or (32) P-ATP showed that CS can be phosphorylated by ATP in Arabidopsis and tomato plants. Gas chromatography-mass spectrometry (GC-MS) analysis using non-isotope-labeled CS and ATP revealed that the phosphorylation of CS occurs at the side chain, most likely at the C-23 hydroxyl. The polar fractions than free brassinosteroids (BRs) obtained from extracts of Arabidopsis and tomato showed almost no BRs activity in a rice lamina inclination bioassay. However, the fractions showed increased bioactivity after treatment with wheat germ acidic phosphatase (WGAP). Additionally, CS was identified from the hydrolysate by WGAP using GC-MS analysis in both plants. In contrast, the polar fractions obtained from BR-deficient mutants, Arabidopsis cyp85a2 and tomato d(x) , did not show an increase in biological activity with WGAP treatment, and no free BRs, including CS, were detected in the hydrolysate. This suggests that CS phosphate is a naturally occurring biologically inactive conjugate that is generated when CS is normally synthesized in Arabidopsis and tomato plants. Taken together, these results suggest that phosphorylation of CS is an important conjugation process for the maintenance of the homeostatic level of an active BR and thus the regulation of the growth and development of plants.

Abstract