Transportation objects include food cold chain logistics, flower, plant cold chain logistics, chemical cold chain logistics and other cold chain logistics. In order to improve the overall performance of the temperature and humidity monitoring equipment in the cold chain process, and further promote and improve the regional metering service system. This study is to analyze its dewpoint temperature stability, relative humidity stability and temperature stability to evaluate the performance of the dew point instrument. The results showed that the standard deviation of temperature, humidity and dew-point in reproducible experiments are 0.00°C, 0.07%RH and 0.01°C. The standard deviation of temperature, humidity and dew-point in stability experiments are 0.02°C, 0.33%RH and 0.066°C. Results show that the measurement method of this experiment meets the requirements of the measurement standards.

With the wide application and rapid development of infrared temperature measurement, which has attracted wide spread interest in the field of non-contact temperature measurement due to its unique advantages. Measurement of the real temperature of the measured object is an important task in many disciplines, especially critical and difficult for the non-contact measurement. However, the accuracy of the infrared thermography technique is difficult to reach a satisfactory level, and cannot meet the requirements of high accuracy, due to the emissivity cannot be determined in outdoor environments. It is very meaningful to determinate the emissivity and accurate temperature of the object in outdoor heterogeneous environments. The influence of external environmental factors on the object surface emissivity are analyzed in this study, which is very important to improve the measurement accuracy of the infrared thermal imaging instrument. This study reveals that the increased temperature will lead in the increase of the emissivity of nonmetallic materials first and then decreases slowly. In addition, as the ambient temperature higher, the emission rate of non-metallic object becomes smaller.