Researches On The Technology Of Grain Moisture Measurement Based On Data Merging

The technology of moisture measurement is a synthetic technology relating to many subjects. During the past several decades, by the researcher's hard work, some prominent successes have been achieved. Whereas, due to the influences of several other factors in moisture measurement, existing moisture instruments have some defects such as ignoring influences by subordinate factors. Hence, the measurement precision and the repeatability are not satisfied. In the thesis, more advanced method of data processing is introduced and exploring study is carried out. These provide new ideas for data processing in the moisture measurement technology. The major points of the thesis include:1.The principles of current moisture instruments are analyzed and their merits and defects are pointed out.2.The capacitive sensor structure is optimized. By comparing various capacitance measurement circuits, a measuring circuit is designed and simulated. The performance of the circuit is practically tested.3.Samples of grain for moisture measurement are made. Data acquisition procedures are planed and executed.4.The relationships of moisture and voltage, temperature and density are indicated by data analysis. The main error sources in the moisture measurement are discussed.5.The data from several type sensors are merged using data fitting method by multi-dimension regressions and artificial neural networks-HP networks method respectively. The particular operating processes are presented and the errors of each methods are analyzed in detail.6.The principle of data merging method based on parameter estimation is used. The validation is proved by increasing the measurement precision and reducing the uncertain factor.