A torque sensing system by using the magnetostrictive ring of FeGa (Galfenol) alloy was developed and magnetic flux leakage from the ring attached on the rotating shaft was experimentally measured. The ring material is the new Galfenol system (FeGaAlC) alloy with higher strength and ductility. The influence of alloy compositions (SK-105 carbon steel, FeGaAlC alloy), rotations speed(250〜1000rpm) on the sensitivity of pick-up voltage from Hall sensor was discussed. As a result, the sensitivity in FeGaAl-C alloy increased by about six times at rotations speed 250rpm in comparison with SK-105, and an almost linear relationship between pick-up voltage and applied toque value was obtained.
In Japan, expansion of economic disparity started at about 1980. This expansion was accompanied by the polarization of Metropolitan Areas. In Tokyo, economic disparity of 23 wards expanded rapidly in 80s. However this disparity reduced temporarily in first half of 90s, because of collapse of bubble economy, expanded again in last half of 90s, and expansion continues until today. In this processes of expansion of economic disparity, socio-spatial structure of Tokyo has changed. On the base of 4-classes scheme, which consists of capitalist, new middle, working and old middle classes, these changes are analysed. From 80s, old middle class dramatically decreased in whole area of Tokyo, especially in central and inner city areas. And in 90s, capitalist class started to decrease in whole area of Tokyo, especially in central area. In these processes, composition of old middle class and capitalist class changed, from family business to one-man management and corporate business. In the result, population of central and inner city area decreased in 80s and 90s. In 00s, new middle class started to flow in central and inner city areas. They filled up the blank of old middle class and small capitalist class, and became the new central player of Tokyo. However this chain of processes can be called gentrification, in the sence that there was some time lag between the exit of old player and emergence of new player, this may be called ‘time-lagged gentrification', which means bloodless revolution by new middle class.
Although consistent stability is desirable, a biped humanoid robot encounters a high risk of falling. Such falls may cause serious damage to both the robot and the environment. This study focuses on this issue and investigates four strategies based on human protective falling motion. These strategies are: "knee flexion", "torso flexion forward", "torso translation backward" and "knee stretched". First, the effectiveness of the strategies for the safe landing is analyzed from an energy variation perspective of the robot system. The four strategies are used to do negative work that reduced the energy of the robot system, thereby reducing the impact velocity of the robot. Then, a simulation study on a human-sized humanoid robot is conducted to assess the influence of the strategies on safe landing. Finally, based on the simulation results for each strategy, a safe falling motion control method is proposed and validated through simulation.
Many patients with TMJ dysfunction suffer from TMJ noise. The measurement of TMJ noise is an important factor in assessing the state of the TMJ dysfunction. Consequently we measured the TMJ noise using electrical techniques in order to make an accurate record. However, determining the side on which the noise occurs is not always easy in auscultation or when picking up the noise electrically, because the sound is carried across the bony structure and picked up on both sides. To solve this problem, we used a three-directional accelerometer, measuring the sound on both sides in the hope that a difference in measurements would allow us to identify the side of the noise. In this study, we vibrated one side of the TMJ with pulse waves, and we compared the vibrated side to the unvibrated side. The height of the pulses was held at 4 volts. In addition, we changed the rising time from 0 volt to 4 volts within a range of 0.6-2.0 msec. The following results were obtained. 1. The time difference between the peaks of the three directions was from 0.32 msec to 3.22 msec on the vibrated side, and from 2.92 msec to 18.2 msec on the unvibrated side. 2. Whenever the time was increased within the selected range, the time difference between the peaks of the three directions on the vibrated side was shorter than that on the unvibrated side. 3. These results suggest that the use of a three-directional accelerometer is a reliable method of distinguishing on which side the TMJ noise is occurring.
Abstract Gasification model developed in Part I is extended to allow for mass transfer of oxidant to the particle and for intraparticle diffusion. For this extension, a moving boundary problem results which is solved numerically in conjunction with a two‐point boundary value problem for the oxidant concentration profile in the particle. The extended model predicts, as expected, that mass transfer stifles gasification and intraparticle diffusion shifts gasification to the outer surface of the particle. For the conditions and parameters used in Part I, particle Thiele moduli above 10 result in particle shrinkage with negligible change in the solid properties, whereas if this modulus is less than 0.1, gasification is kinetically controlled.
