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This paper suggests the novel algorithm for the estimating gait parameters of the hemiplegic patients using a 3-axis accelerometer. The signal processing for algorithm consists of a bandpass filter and a least square acceleration filter. To evaluate the performance of the algorithm, the correlation coefficients of the stride and the step time between the 3-axis accelerometer and the Vicon motion analysis system are compared. In consequence, correlation coefficient ranged from 0.90 to 0.99 for patients and ranged from 0.92 to 0.99 for normal subjects. The results showed that the novel algorithm is very useful for estimating not only hemiplegic gait but also normal gait.

Accurate estimation of the body center of mass (COM) location has important clinical ramifications in locomotion associated with daily activities of living (ADL). This paper compared two computational estimation methods of COM using an accelerometric measurement and a VICON motion analysis system measurement (established or golden standard), respectively. A convenient sample of four healthy subjects participated. The body COM was measured when the subjects walked on the 6-m long walkway at their self-selected speed for 5 trials. VICON and accelerometer COM data signals were computed by VICON Polygon and trapezoidal double integration methods, respectively and compared to determine the concurrent validity of our COM estimation method. Correlation statistics showed excellent relationship between the two methods (r =0.87, P< 0.05), reflecting an acceptable validity. Our results suggest that the COM estimation using the accelerometer method is as accurate as the conventional method and provide clinical insights when designing a portable and inexpensive COM measurement tool for locomotion evaluation.

A polarization-independent multilayer dielectric diffraction grating with a low aspect ratio and high diffraction efficiency was designed and fabricated. The diffraction grating designed with a grating density of 1200 lines/mm had an aspect ratio of 0.59, mean polarization-independent diffraction efficiency in the Littrow angle of ± 2.5 ∘ , and 1030–1080 nm wavelength range of 97.2%. The designed grating was fabricated using ion assisted deposition and reactive ion etching techniques. The mean polarization-independent diffraction efficiency of the fabricated grating was 96.1%, and its standard deviation was 0.68%. The fabricated diffraction grating was irradiated with a 1064 nm cw laser, with a power density of 30 k W / c m 2 , for 1 min to measure the temperature change before and after the laser application. It was verified that the temperature variation of the diffraction grating without heat treatment was 8.8°C, and the temperature variation after heat treatment at 400°C decreased to 2.3°C.

We developed a novel radio-frequency (RF) stimulator to mimic heat effects similar to the temperature distributions created by moxibustion in porcine tissue. Moxibustion is a traditional Oriental medicine technique using moxa, which is utilized not only to cure disease, but also to increase immunity. However, it may lead to undesired effects including severe pains, blisters, and burns because of the difficulty of controlling heat intensity during the process. To overcome these problems, a novel RF stimulator that can conduct thermal energy to the deep tissue of the body and also easily control the power of heat stimulation was proposed. RF stimulating protocols were designed to mimic the temperature profiles of two types of moxibustion. In our results, the temperature distributions created by the proposed protocols were similar to those attained by moxibustion. It was also shown that the proposed protocols were more effective than moxibustion for transferring heat effects into deep tissues.