Abstract:The ground temperature changes at a rate of 0.1 ℃ every 10 years,however,a solar radiation error of about 1 K can be produced by conventional radiation shields due to the influence of solar radiation.In order to improve the accuracy of surface temperature measurement and reduce working energy consumption,this paper designs a temperature sensor based on the accelerated diffusion of radiant heat via piezoelectric ceramic vibration.First,the Computational Fluid Dynamics (CFD) method is used to calculate the radiation error of the temperature sensor under multi physical factors,then the data is fitted and analyzed using the neural network algorithm,and finally the field experiment platform is built to place the temperature sensor in real environment to verify the feasibility of the scheme.The experimental results show that the absolute error and root mean square error between the corrected value and reference value of the surface temperature sensor are 0.041 ℃ and 0.055 ℃,respectively,which also verifies the superior correction performance of the neural network algorithm.

Abstract:In order to solve the problem that the temperature sensor is susceptible to humidity during measurement,this paper takes some improvement researches into advolution operation,alienation operation and convergence conditions in mind evolutionary algorithm,and makes some adaptive adjustment of the distributing weights in the convergence operation.Differential operation is introduced into alienation operation and the situation with flat searching plane is considered.A humidity compensation method using improved mind evolutionary algorithm of BP neural network model is established,according to the sample data obtained from the experiment of humidity influence.Compared with general BP neural network model,the improved mind evolutionary algorithm of BP neural network model has higher compensation precision,faster convergence and less computation load,which can improve the accuracy and reliability of the temperature sensor effectively and is convenient for applications.

Abstract:With the increasing attention focused on the measurement accuracy of the high altitude air temperature,it is necessary to research into the source of the radiosonde temperature sensor error.Solar radiation makes the most significant contribution to the error in upper air temperature measurement.A computational fluid dynamics(CFD) method is employed to study the errors induced by solar radiation and lead angles,from sea level to 32 km altitude.The results show that lead angle and solar incident angle are important factors that affect the errors.Simulation results can be used as a reference for error correcting,which has a potential to improve the measuring accuracy.

Abstract:Based on 12 flight dataset from the 8th WMO international radiosonde intercomparison hold at Yangjiang of Guangdong province,the systematic evaluation of 3 types of bead resistance temperature sensor for China-made radiosondes,which belong to CHANGFENG,HUAYUN and DAQIAO company respectively,is carried out by choosing Germany GRAW radioseonde as reference through the same balloon releasing model.The initial evaluation results show as following:1)The 3 temperature observation profiles of domestic radiosondes have good consistence with that of Germany GRAW radiosonde,with better performance at nighttime than at daytime;2)CHANGFENG temperature sensor has better stability,whereas HUAYUN temperature sensor and DAQIAO temperature sensor both decrease in performance with height increase,particularly above 30 km;3)CHANGFENG temperature sensor has the best performance,whose relative systematic error is about 0.2℃,whereas the relative systematic errors of HUAYUN temperature sensor and DAQIAO temperature sensor can reach 1℃.So bead temperature sensor may be a good choice for future upper-air temperature detection,but the coating material and radiation correction algorithm for HUAYUN temperature sensor and DAQIAO temperature sensor need to be further improved.

Abstract:A modular Renesas singlechip experimental system is developed to design digital thermometer.The system uses highly integrated temperature sensor,adopts modular design scheme and completes the thermometer design which is based on 16-bit singlechip microcontroller(M3062LFGPGP).A new algorithm is introduced to process temperature data.Temperature measuring precision could be improved by using main control software and appropriate hardware correction technique.According to traditional design principles and the characteristics of Renesas microcontrollers M3062LFGPGP,the system integrates A/D converter module and calendar module into the main control module,and uses software program instead of the above-mentioned two hardware modules and realize their functions simultaneously.The system consists of control module,temperature module and display module.The system can display the current temperature with time like year,month,day,week,hour,minute,second,etc.This design can significantly reduce systems power consumption and decrease hardware design errors,thus improve system stability.This digital thermometer can accurately measure and clearly display the current temperature and time,which is highly valuable in application.