Support Vector Machine To Identify Drugs And Antibiotics Terahertz Spectroscopy

The terahertz (THz,10¹²Hz) wave, categorized between millimeter radio waves and farinfrared light wave, with a frequency lying in 0.1THz and 10THz, belongs to far-infrared band.Since it possesses many attractive properties, the studies of its applications have been paid moreand more attentions. It is believed that THz technique has a good future in many fields, such asphysics, chemistry, biological medicine, communication, radar, security inspection, etc. Thisthesis, based on THz-TDS technique, a frontier subject, mainly focused on spectrum applicationsand identification arithmetic.The main work of this thesis was proposed in chapter four and chapter five.In chapter four, based on the absorption spectra in the range from 0.2 to 2.0 THz of nineillicit drugs using Terahertz time-domain spectroscopy technique, the THz absorption spectra offive different illicit drugs and three mixtures were identified successfully by Support VectorMachine(SVM) . With the Beer-Lambert law, contents of the mixtures were analyzed. In chapterfive, the THz absorption spectra of five antibiotics were identified successfully by SVM. Theresults indicate that it is feasible to apply SVM on the identification of illicit drugs andantibiotics, and provide an effective method in the secure inspection and identification for illicitdrugs and western medicine using THz time-domain spectroscopy technique.