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Walking trolleys that are currently being manufactured have a function that prevents downslope movement when the user crosses a slope. In this study, we have developed a test method to evaluate this function. First, we measured the handle-operating force exerted by elderly persons when crossing a slope by carrying out an experiment with 17 elderly participants. Analysis of the results indicated that the handle-operating force was 28 N. Based on these results, we developed a test method and a test equipment. Furthermore, we used the test equipment to conduct experiments on walking trolleys with and without activating the assist function to validate the test method. It was found that the proposed test can be performed with sufficient accuracy.

Manufacturers have recently been developing assistive walking devices with electric motors, based on rollators and walking trolleys, in Japan. These assistive devices have electric motors to assist walking on sloped surfaces. Furthermore, they have a function that automatically suppresses the speed on downhill slopes. Here a walking experiment was conducted to investigate the speed at which the suppression function needed to be applied in various walking conditions. The subjects in the experiment walked while leaning on the assistive device, applying forces of 37 (horizontal) and 204 N (vertical) on downhill slopes. Furthermore, an analysis of the walking data obtained from traditional walking trolleys revealed that 80% of the subjects walked at a speed of 2.5 km/h or more. Two experiments were conducted to develop a test method that analyzed the performance of the suppression function on downhill slopes. The proposed test method results yielded sufficient accuracy.

In physical assistant robots used to mitigate burden on the lumbar, there is a risk that if the assist torque is lost, excessive burden may be applied to the lumbar. Therefore, for some products, a system to lock the moving parts on the lumbar is examined as a prevention measure against this risk. Through an experiment on a subject who wears test equipment that simulates a physical-assistant robot, the myogenic potential at the lumbar when the assist torque was lost was measured. Results indicated that if the moving part is locked within 151 msec after the loss of assist torque, the load of the lifted baggage can be supported by the frame of the robot and thus the burden on the user can be mitigated.

In order for manufacturers of robotic devices for nursing care to predict injury in accidents related to their products, risk assessments are carried out according to various standards e.g. ISO 12100. Probabilities of death, bone fracture and head injury are estimated by analysing data published in Japan and U.S.

Human foot injury due to being run over by a robot is a hazardous event caused by robot motion. This study aims to provide information for the safety design of robots in terms of the risk of foot fracture. A model for scaling the fracture loads of alternate specimens (bear metatarsals) to those of human metatarsals considering the effects of soft tissue is proposed and validated. Using the model, fracture tolerance of metatarsals of a human female foot of statistically typical size is predicted to be 1.24 kN at 10% fracture probability, and 0.53 kN at 1% fracture probability with 95% confidence.

Microscopic dynamical properties of traffic flow are studied from the aspects of vehicle behavior and driver operation. We studied the nature of fluctuations around the critical region in real traffic by analyzing a time series of variations of velocity obtained from single-vehicle data measurement. We found that the probability density function calculated from the time series of velocity variations is transformed, while a Gaussian distribution transitions into a stable symmetrical Levy distribution. The power-law tail in the Levy distribution indicated that the time series of velocity variation exhibits critical fluctuations. The power-law tail in the probability density function suggests that dynamical processes of vehicular traffic are related to a time-discrete stochastic process driven by random amplification with additive external noise. In contrast, the empirical data of deceleration in a car-following situation obtained from the driving simulator experiment indicated a large dispersion of perceptual quantities of a driver when operating the brake pedal. The result suggests that the algorithm for operating the brake pedal is closely related to the random amplification in the discrete stochastic process.

Effects of hands-free phone conversations on drivers' visual behavior and detection performance were examined using a gaze-tracking device and fixed-based driving simulator. The participants engaged in various conversation tasks (simple/arithmetic/unconstrained) while following a lead vehicle. The results indicated that hands-free-phone conversations, even if the contents are not subjectively demanding, can affect a driver's visual behavior. The increment of binocular gaze dissociation induced by conversing on a phone indicates that a driver's attention is diverted from the external scenery to the conversation. Furthermore, this observed dissociation of binocular gaze may represent a resting position, which is revealed only when binocular fusion is disrupted by occluding one eye.

The photoluminescence (fluorescence) of a film of the laboratory-synthesized quenched carbonaceous composite (filmy QCC) is shown to have a single broad emission feature with a peak wavelength that varies from 670 to 725 nm, and coincides with that of the extended red emission observed in reflection nebulae. The rapid decay of the filmy QCC red fluorescence in air and of the stable blue fluorescence of the filmy QCC dissolved in liquid Freon suggests that the red fluorescence originates from the interaction of active chemical species and aromatic components in the filmy QCC. A material similar in nature to that of the filmy QCC may be a major component of interstellar dust.

Pt (II) complexes of 4-substituted o-phenylenediamine (opda-R ; R=CH3, OCH3, H, Cl, COOH, NO2, and SO3H), PtX2 (opda-R), were synthesized and tested for antitumor activity against P-388 leukemia. The infrared spectra of those complexes were analyzed to assign the Pt-N stretching vibrations on the basis of the halogeno trans effect and Hammett's σ values. The assigned Pt-N strectching vibrations were related to the antitumor activities of the opda-R Pt (II) complexes.

Suburbanization is very phenomenal in the western suburbs of Tokyo, nevertheless a. sizable area is still devoted to agriculture and the agricultural output is quite large. The aim of this research is to survey the ecological aspects of human occupance of the land which is well characterized by the ever intensive urban as well as agricultural use and also to analyze operational structure of farm households that has strongly led the study area to such a suburbanized occupance pattern in terms of interviews of farmers and various statistical materials.Results : 1) Sale of agricultural land is quite limited because of rise of land price, resulting in the juxtaposition of built-up areas and farmlands. 2) Agriculture in these mostly built-up areas has the following characteristics : a) to increase labor productivity rather than land productivity, b) to increase household or personal income whether by specialization on arboriculture, lawn growing, specialized vegetable growing and chicken and pig raising, or by incorporating them in agricultural management so as to improve total agricultural productivity, or from other sources than farming such as management of filling stations, driving, schools, and public baths, and also as white color, c) to hold agricultural land as assets probably for a relatively long period, since the farmers here can get stable income from rent and apartment houses they have built recently, although increment of so-called socially fallow lands is to be seen frequently, and d) to ship out vegetables and eggs to nearby markets or to sell them directly at farmsteads. 3) It is urgently needed to conserve as much farmland as possible and also even to encourage farm management to a degree that the farmers are able to compete with ever-developing urban industries, otherwise the critical shortage of green open spaces in the metropolitanized regions will be further accelerated.