The present paper is concerned with a review of the recent research aspects of vehicle safety in U. S. A. from the view point of human factors. These aspects were divided into two fields; (1) safety in collision, (2) accident prevention. The former was discussed in terms of biomechanical and mathematical approaches, and the latter in terms of vehicle design, drivers, and other factors.

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A rational classification of terms related to the sense of touch by means of semantic differential was carried out. Consequently, we could plot a few psychophysical functions in graphic forms.
Next, the correlations between psychological and physical scales were calculated and factor analyzed. The first factor has high loadings on scales, especially in not elastic, hard, stiff, sharp, painful, cold, not plastic, heavy etc. The second factor has high loadings on scales, especially in wet, smooth etc. The amount of variance accounted by first two factors amounted to 71%. Therefore, surface touch seems to be relatively simple.

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A half century or more ago in our country, almost tools for domestic, farmer's or wood-craft use were made by hand, fitting shape or size to user's hand or body for the easy use.
These hand-made folk tools seems to have much value when we project the spot light of ergonomic aspects.
The hand-made folk-tools are, however, rapidly extincting especially from the Second World War, so that we searched them in several local museums or in remote districts mainly in South-Western Japan and collected the measurements of size, shape and weight of 853 hand-made tools and also photographed them.
In the present paper, we deal with the shape and size of grasping portion, and correlation between their figures.
The results are as follows: 1) The vertical section of grasping, generally draws, a circle or an ellipse. (It's vertical length is larger than horizontal one.) 2) Concerning more productive farmer's and wood crafter's tools, the size of grasping portion measures 20-35mm in horizontal diameter, 25-40mm in vertical diameter, the girth is 85-115mm. 3) There is a significantly high correlation between the tool's handle length and it's position of the center of gravity.

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Among the various factors the position of saddle and handle which decide the cycling posture, the crank length and the gear-ratio are most important factors for the best cycling. For the first time we made some experiments on the influence of the gear-ratio to the maximum speed and the best mechanical efficiency of cycling. In order to research the most effective gear-ratio we measured the O₂-consumption, heart-rate and the work done by the rider (1) in his full-speed cycling of 1000 meters and (2) in the steady state at various speeds, by using the bicycle test stand specially designed. The O₂-concentration of expired gas was continuouslymeasured by the O₂-gas analysor of Nihon-Gaishi Company.
The diagram of O₂-consumption against every gear-ratio in various constant speed and the diagram of the lap-time against every gear-ratio resembled each other in different individual. It was deduced from the diagram that the best gear-ratio for the most efficient and speedy cycling was in general higher than usual one.

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On human engineering to learn eye-movement is very useful. As the techniques to know eye-movements, an eye-marked camera and EOG (Electro-oculograph) are popular today.
The authors developed a simple EOG equipment and some experiments with it are performed. The eye-movement while reading a book is discussed and the effect of drinking on reaction time of eye-tracking is analized.
Other experiments are not concerned with eye-movement but with wink.
Normally the period between winks is less than 10 seconds, but while dozing, winks disappear. Then, by detecting the period between winks, it is possible to alarm.
The apparatus was produced and it is supposed that some other applications are possible in the studies of human engineering.

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Layout of the signal switches of the Centralized Traffic Control Room was studied, since operation errors were often observed presumably due to their inconsistency with the panel display. Switching operations were 14% of actual operation time in the daytime. The polygram recorded during the train control indicated elevated mental load for the switching of signals. In order to avoid the confusion, a new layout of the switch-board for some stations were recommended. It could be realized by rather simple reconstruction and helps operators check the route to be taken more easily, as it gives a functional and logical connection of switches with the panel display.

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