For establishment of evaluation method on one shot shock motions generated jumping down in prefabricated private houses, feeling of shock on jumpimg was equalized to sensation of one shot model pulse on the vibration table. The model. pulse signals were made by a C-R discharge circuit starting with a monostable multivibrator and its wave shapes were varied by changing time constants of the C-R circuit. It was found that one shot of the model shock with longer duration produced larger sensation than that with shorter duration. It was also noticed that the smaller level of one shot shock motion caused weaker sensation than the larger level of it.
Then, the sensation of one shot of these model pulses was equalized to that of a sinusoidal vibration at 10 Hz. A relation between the level of the sinusoidal vibration (dBAL) and logarithmic value of the duration of pulses was derived through a parameter of amplitude of the pulses. Using this equation, the equal sensation level of sinusoidal vibration for actual pulses could be estimated, which. agreed with the values observed directly.
One shot model shock of which durations were changed at 40, 60 and 100 ms and levels at 6 grades from 95 to 120 dBAL was rated on a psychological evalua tion scale in 5 steps. The sensation at the third step of "unpleasant" corresponded to 114 dBAL for one shot shock with the duration of 40 ms, to 116 dBAL for 60 ms and to 119 dBAL for 100ms.
Thus, a clue of solution for an evaluation method for one shot pulse was pre-sented.
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