Both leaf and root conditions are important aspects of commercial radish (Raphanus sativus var. sativus) quality. We thus investigated changes in radish respiration rate, leaf color, and root quality after 6-days of storage under 24 different conditions combinatorially incorporating 4 different temperatures (5, 10, 15, and 20 °C) and 6 different oxygen (O2) concentrations (20, 16, 12, 8, 4, and 2 %). Respiration (CO2 production) rates (Rsp) were reduced by low temperature and low O2, and a relationship between temperature (T) and O2, and the respiration rate could be expressed as Rsp = 2.58T + 0.64O2 − 8.43 (R = 0.96). The partial regression coefficient for temperature was approximately 4 times the O2 concentration, indicating that the effect of low temperature was greater than that of low O2. A decrease in leaf color was inhibited by both low temperature and low O2. Root color was not affected by differences in O2 concentration or temperature. Low temperature was more effective at inhibiting rootlet development than low O2. These findings suggest that low O2 exerts less effect than low temperature. Therefore, a low temperature (10 °C or 5 °C) is necessary to maintain radish commercial value.

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A random vibration test is important for confirming the safety of packaging on a truck bed during transportation. There are differences between the random vibration generated by the traditional method and the real vibration measured on a truck bed. Multiple studies have been performed to improve the generation of vibrations during testing. These methods are broadly divided into two categories: non-stationary and stationary. Since advantages and exist for both methods, they need to be compared under the same conditions. To date, there are no studies that compare stationary and non-stationary methods. Herein, seven different methods (both stationary and non-stationary methods) are used to generate vibrations. The generated vibrations are evaluated by statistics, the moving root mean square, and the kurtosis response spectrum. In terms of the kurtosis response spectrum, the kurtosis response method (a stationary method) is the closest to the real vibration, especially when the damping factor is low.

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