SUMMARYAn update on the nature of shock and vibration in truck transport was obtained by measuring and analysing the shock and vibration levels separately that occur during truck transportation in Japan. The effect of truck speed on the shock and vibration levels was mainly analysed. A signifi cant difference was observed between the acceleration of vibration, and the acceleration including shock and vibration as a result of truck speed. The results indicated that the effect of truck speed on root mean square acceleration (Grms), including shock and vibration, was strong at a lower speed, but slight at a higher speed. The highest Grms, including shock and vibration, was found at 45-59.9 km/h on local roads, which was higher than that during highway driving. When the speed was below 45 km/h, the peak power spectral density (PSD) of acceleration including shock and vibration increased as truck speed increased; when the speed was above 45 km/h, no signifi cant changes in peak PSD were found because of truck speed. At the same time, the effect of vehicle speed on the vibration acceleration was also studied. It was found that the higher the vehicle speed, the higher the Grms and peak PSD value of vibration in both the vertical and lateral directions.

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To propose potential lab-simulated vibration tests for developing appropriate cushioning packaging, we recorded vibration acceleration during truck transport, including large sporadic shocks in regular smaller vibration so that acceleration did not cover a normal probability distribution and could not be considered as random vibration. We extracted all shock acceleration from vibration during local road and highway transport and studied the causes. We found that shocks were caused by road roughness, metal joints, difference in levels on the asphalt-surfaced road, pedestrian crossings, manholes, road curves, left and right turns, railroad crossings, etc. After removing shock events from all vibration acceleration during transport, we reconstructed remaining acceleration as continuous vibration. Vibration acceleration followed the normal probability distribution and could be considered random.

The Stirling cycle engine was invented almost 190 years ago. In this study, the reverse Stirling cycle is investigated for use in refrigeration. This type of cycle is referred to as Stirling cooling or cooler. An experimental free-piston Stirling cooler (FPSC) was constructed and the effects of the device parameters in relation to the performance of the cooler were studied; the equipment was then experimentally applied to churning butter. Two effect parameters, namely, the size of the displacer involving heat regeneration and the volume of the working fluid (air) were studied. The results indicated that a larger displacer resulted in a lower temperature in the cooler. When the working fluid volume was large or the compression ratio was high, the cooling effect was enhanced. It was concluded that by churning butter using the Stirling cooler, coagulation of the butter occurred more rapidly than when the contral was used in the process; the water content of the butter obtained was lower and the fat content was higher using the Stirling cooler. This implies that the feasibility of using the Stirling cooler for churning butter is high.

The possibility of near infrared (NIR) spectroscopy to measure the amount of bacterial contamination in shredded cabbage was investigated. NIR measurements in the short wavelength region from 700 to 1100 nm were done using two types of saline solutions: one was used to stomach with the samples as the conventional method and the other was used to wash the outer surface of the sample to examine the possibility of a nondestructive method. Partial least squares regression (PLS) was used to develop the equations for bacterial amount. Spectra from the stomacher solution and the washing solution produced similar results. Sufficiently accurate results could be obtained with the bias-corrected standard error of prediction (SEPs) of 0.46 log CFU g )1 for the stomacher solution and 0.44 log CFU g )1 for the washing solution. NIR spectroscopy was clarified to be a rapid and non-destructive method for prediction of bacterial contamination in shredded cabbage.