Research On The Method Of Material Recognition In ZD System Of X-ray Transmission Imaging Machine

In recent years, with the continuous development of the postal services, the post office is facing the challenge of the difficult security situation, how to improve the security level of the parcels become increasingly important. X-ray equipment has been confirmed has the ability of revealing molecules or atomic properties of a material, this feature is very important to detect dangers. This paper is based on the existing post office central office work processes, using radiographic detecting technology of dual energy X-ray to research the identification of dangers. Dual energy X-ray detection technology is widely used in security equipment, as it can acquires the effective atomic number of the material is detected and obtains real grayscale by removing the shade, those provide the basis for identifying danger. Although this technology has been commercialized, but the mostly is not mature yet. The detected material is divided into organic, inorganic and mixture type, but it can’t identify the dangers from the safe materials. This essay is research an effective method based on dual energy X-ray radiographic detecting technology.This paper summarized the components and principle of dual energy radiographic detecting system in first, understanding deeply the principle of the detector and the influence of its properties on material classification. And so, studies the basic principle of material classification and analysis the features of high and low energy grayscale level, puts forward the dangerous goods identification algorithm. The overlapped mathematical model is established and verified by experiment.The fourth part is most important, according to the classification principles of the third chapter to determine the experimental programs. The experiment scheme is formulated according to danger identification algorithms, collecting the date of high and low energy grayscale and fitting the curve, gets the identify curve and mathematical model on the basis of high and low energy grayscale. Through a variety of material and random thickness of gunpowder experiment, verify the feasibility of the curve identification. Do the experiment of gunpowder in different backgrounds, calculating the real grayscale of gunpowder by overlapped mathematical model, further verifying the feasibility of the overlapped model. Put forward the simulation domain model of dangers identification. Based on the above theory and experiment, develop automatic identification software of dangers, the function of acquire the high and low energy of identified points, the average grayscale of rectangular domain and automatic identification alarm are realized.The mainly work of the paper are proposed a dangerous identification method and developed dangers automatic identification software based on dual energy X-ray radiographic detection technology.