This paper presents the temperature-pressure characteristics of a newly developed SMH actuator using hydrogen-absorbing
alloys. The new special metal hydride(SMH) actuator is characterized by its small size, low weight, noiseless
operation, and compliance similar to that of human bodies. The simple SMH actuator, consisting of plated hydrogen-absorbing
alloys as a power source, Peltier modules as a thermal source, and a cylinder with metal bellows as a
mechanical functioning part, has been developed. An assembly of copper pipes has been constructed to improve the
thermal conductivity of the hydrogen-absorbing alloys. It is well known that hydrogen-absorbing alloys can reversibly
absorb and desorb a large amount of hydrogen, more than about one thousand times of their own volume. By heating the
hydrogen-absorbing alloys, the hydrogen equilibrium pressure increases due to desorption of hydrogen, whereas, by
cooling the alloys, the hydrogen equilibrium pressure drops due to absorption of hydrogen by the alloys. The new SMH
actuator utilizes the reversible reaction between the thermal energy and mechanical energy of the hydrogen absorbing
alloys. To be able to use the SMH actuator in medical and rehabilitation applications, the desirable characteristics of the
actuator have been studied. For this purpose, the detailed characteristics of the new SMH actuator for different
temperature, pressure, and external loads were explored.
We propose a nonlinear matching measure, called counting measure, as a signal detection measure that is defined as the number of on pixels in the spot area. It is applied to classify probes for an on-off type DNA microarray, where each probe spot is classified as hybridized or not. The counting measure also incorporates the maximum response search method, where the expected signal is obtained by taking the maximum among the measured responses of the various positions and sizes of the spot template. The counting measure was compared to existing signal detection measures such as the normalized covariance and the median for 2390 patient samples tested on the human papillomavirus (HPV) DNA chip. The counting measure performed the best regardless of whether or not the maximum response search method was used. The experimental results showed that the counting measure combined with the positional search was the most preferable.
We propose a new nonlinear matching measure for automatic analysis of the on-off type DNA microarray images in which the hybridized spots are detected by a template-matching method. The proposed measure is obtained by binary thresholding over the entire template region and taking the number of white pixels inside the spotted area. This measure is compared with the normalized covariance method in terms of classifying the ability to successfully locate markers. The proposed measure was evaluated for scanned images of human papillomavirus (HPV) DNA microarrays where locating markers is a critical issue because of the small number of spots. The targeting spots of HPV DNA chips are designed for genotyping twenty-two types of the human papillomavirus. The proposed measure is proven to give a more discriminative response, reducing the missed cases of successful marker location. The locating accuracy of the proposed method is also shown to have the same performance as that of the normalized covariance.