"These moves have a powerful deterrent effect," Wang said.
Feedback from parents and schools was said to be positive, with teachers praising them as an effective deterrent.
After six months of work, he came up with the SkunkLock, a hollow steel U-lock system which houses presurized noxious chemical deterrent that's even detectable through some of the most advanced gas masks.
It is aimed to be a deterrent, a way to discourage people.
One deterrent is cost: the company which makes the machines, Singapore-based Unitech Mechatronics, sells them for S$47,000 (US$34,340).
Setting up a network would also drain the batteries of connected phones, a deterrent factor.
" However, another banker said that CFIUS's tough stance on Chinese takeovers would not prove a deterrent for Beijing-backed buyers.
Arrivals will continue until an adequate deterrent is put in place: the landing of every single migrant not on European soil but in a transit centre in Tunisia or Egypt, from where opportunistic migrants can be separated from genuine refugees and repatriated.
"It doesn't bother me, but I can see how that would be a huge deterrent for a lot of people.
To be slapped on the wrist doesn't hurt much, and isn't a deterrent from misbehaving again.
