A Team Serves Security Check System for Public Safety

A team called the Tiny Little Inspection from the College of Optical-Electrical & Computer Engineering of USST won the the Grand Prize at the 16th Challenge Cup: Shanghai Undergraduate Curricular Academic Science and Technology Works Competition.

“The existing metro security inspection system uses X-ray to detect large luggage, while some containers such as beverage bottles can easily escape from the security check, which gives criminals the chance to carry dangerous liquid contraband into the subway,” Song Ruixin, one of the team members said. They recognized the importance of public safety and decided to work on it. Based on terahertz time-domain spectroscopy (THz-TDS)，they designed the Portable Terahertz Dangerous Liquid Detector which successfully identified bottled liquid in rapid scanning. This detector was intended for security policemen to quickly and accurately distinguish between safe and dangerous liquids at all kinds of public entrances. After continuous perfecting, it can be applied with high detection efficiency, convenient operation and good stability to densely populated places such as in metro stations.
Apart from their clear objectives and excellent skills, their team spirit also contributed to their success. They all believed that it was their persistence and patience that made the team successful.

Song Ruixin said: “Some excellent students with more experience were involved in this competition, but they could not overcome difficulties and had to give up.” It was an arduous year when they had to collect countless data and they did boring and repeated tests, but they stuck to finishing all tasks. Besides, he also benefited a lot from the competition. He learnt something that he could not acquire in the classroom, such as some skills in debating and in different kinds of communication, which was useful for his future development.
Jiang Yixin, another team member, told us that: “The process was indeed very boring. We tested over a thousand kinds of drinks and collected relevant information. When you were in the same process every day: scanning, marking, and comparing the results, you might feel tired of what you were doing and probably would fail to achieve the goal. We never complained about what we had to repeat. Patience was the key to our success.” She told us that she became more patient than ever before.
Fan Xinyi, the leader of the award-winning team, stressed：“We had a clear division of work so that each member shared his or her own responsibility. We made sure that everyone was in charge of what they specialized in so that we could complement each other.” She also mentioned that during the cooperation process she built precious and unforgettable friendships with other team members. When preparing for the competition, the whole team would go out for a dinner or karaoke to relieve pressure. At the same time, it strengthened the relationship among the team members.
Having won a Grand Prize at the Shanghai competition, they never felt conceited but were glad to learn from the feedback given, and then continued to refine the design, making it more competitive for the coming national competition. Song Ruixin told us: “We ignore influences the electricity of the experiment venues will have on our detector, because our tests are usually conducted in the laboratory, or some outdoor venues at USST. We still need to improve the property of the detector to avoid mistakes that may occur.” They are positive about the national competition and hope that the detector will come into use around the world as it is getting more accurate and convenient.

The Portable Terahertz Dangerous Liquid Detector