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In order to measure temperature accurately the authors deduced a general computing formula for the measurement of surface temperature with an infrared thermal imager according to the principles of thermal radiation The authors analyzed the conditions for an accurate measurement of temperature with an infrared thermal imager and emissivity's influence on accurate measurement of temperature The authors also studied the influence of the environment atmosphere and the thermal imager on the accuracy of temperature measurement In addition the authors drew a theoretical curves of various factors influencing the accuracy of temperature measurement The result of the study reveals that when the emissivity is 0.7 the actual temperature is 50 and the deflection of emissivity is 0.1 then for the 3~5ȝm thermal imager the deviation of measurement from the actual temperature is 0. 76~0.89 and for the 8~14ȝm thermal imager the deviation is 1.56~1.87 The result of the study is of practical significance for improving the accuracy of the measurement of temperature and surface emissivity Key words-infrared thermal imager; measurement of temperature; error analysis; emissivity . INTRODUCTIONThe infrared thermal imager provides an effective and rapid method for real-time measuring of surface temperature, which has obvious advantages over other measuring methods in the following two cases:(1) To measure the surface temperature of the target object with a large area and heterogeneous temperature distribution; and (2) To quickly locate the hot spots or hot areas of the target object in a limited area. Because the accuracy of temperature measurement with infrared thermal imagers is influenced by emissivity and reflectivity (or absorptivity) of the surface of the object, ambient temperature, atmospheric temperature, measurement distance, and atmospheric attenuation, the application of infrared thermal imagers in some cases are directly affected. For example, during the temperature measurement of PCB circuitry [1] , due to the wide variation range of emissivity, it is necessary to adopt different types of analytical software using different emissivities for every pixel of the thermal image. Having studied such influencing factors as emissivity, reflectivity (or absorptivity), ambient temperature, atmospheric temperature, measurement distance and atmospheric attenuation, Yang Li et al summarized the effects on the infrared temperature measurement caused by the measurement errors of the above factors [2][3][4][5] . Zhang Jian et al analyzed the influence on the deflection of the infrared temperature measurement caused by nearby high-temperature objects 6 .In the aspect of scientific experiment and research, the thermal infrared imager also demonstrates its advantages in temperature field measurement of target objects. For example, with the help of the thermal infrared imager, Wang Xishi et al measured the temperature of flame [7] , Hou Chenggang et al accurately measured the emissivity of objects [8] , and they both obtained good results. At...

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This paper introduces the main problems in the air conditioning system of China’s textile mills. Due to the coupled line problem of temperature and humidity affecting each other in the temperature and humidity regulation system, it is difficult to adjust the air conditioning system in the textile mill, and it is also more difficult to adjust the air conditioning system in the textile mill because of the influence of region, season, human activities and so on. In view of this situation, the air conditioning control system of textile mill based on TMS320F28335 was designed by dynamic decoupling control method. The reasonable adjustment and control of the equipment of the air conditioning system can achieve the stable control of the temperature and humidity of the workshop of the textile mill and reduce the energy consumption of the air conditioning control system. The practice shows that the system has good dynamic performance, high control precision and remarkable energy saving effect, and has a broad application prospect in air conditioning control in textile enterprises.