In this paper, we propose a pulse-Doppler radar system for in-home gait assessment of older adults. A methodology has been developed to extract gait parameters including walking speed and step time using Doppler radar. The gait parameters have been validated with a Vicon motion capture system in the lab with 13 participants and 158 test runs. The study revealed that for an optimal step recognition and walking speed estimation, a dual radar set up with one radar placed at foot level and the other at torso level is necessary. An excellent absolute agreement with intraclass correlation coefficients of 0.97 was found for step time estimation with the foot level radar. For walking speed, although both radars show excellent consistency they all have a system offset compared to the ground truth due to walking direction with respect to the radar beam. The torso level radar has a better performance (9% offset on average) in the speed estimation compared to the foot level radar (13%–18% offset). Quantitative analysis has been performed to compute the angles causing the systematic error. These lab results demonstrate the capability of the system to be used as a daily gait assessment tool in home environments, useful for fall risk assessment and other health care applications. The system is currently being tested in an unstructured home environment.

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2015)Design and control methodology of a 3-DOF flexure-based mechanism for micro/nanopositioning. Copies of full items can be used for personal research or study, educational, or not-forprofit purposes without prior permission or charge. Provided that the authors, title and full bibliographic details are credited, a hyperlink and/or URL is given for the original metadata page and the content is not changed in any way.

A series of xMnyCe/hexagonal mesoporous silica (HMS) sorbents with wormhole-like structure was prepared by a sol−gel method, and their performance for hot coal gas desulfurization was investigated at 600 °C. All xMnyCe/HMS sorbents exhibited high breakthrough sulfur capacity, and the utilization of these sorbents was much higher than that of 10Mn/HMS. The breakthrough sulfur capacity over 4Mn1Ce/HMS sorbents was 121.7 mg of S/g of sorbent with the utilization of 82.4%. Such a behavior was maintained in eight consecutive desulfurization−regeneration cycles. The effects of the desulfurization temperature, H 2 concentration, and 7% steam on the performance of 4Mn1Ce/HMS were examined. The fresh, used, and regenerated samples were characterized by means of X-ray diffraction, N 2 adsorption, Fourier transform infrared absorption spectroscopy, and high-resolution transmission electron microscopy techniques. The results confirmed that the manganese oxide was dispersed highly on the HMS support because of the synergetic effects of manganese oxide and ceria oxide, and the wormhole-like structure in sorbents promoted the diffusion of H 2 S molecules. The Brunauer−Emmett−Teller results revealed that the wormhole-like mesoporous structure in sorbents remained intact even after the eighth successive desulfurization/regeneration cycle.