Zero-knowledge proof is a very interesting problem in modern cryptography, which attracts the attention of many cryptographers, and there are plenty of researches. It is one of the hot research field in cryptography. First, we made a simple introduction of zero-knowledge proof. Then we had given a perfect quantum zero knowledge proof system on a specific NP… (More)
This paper adopts the theory of the axis symmetry column thin shell to analyses the instance that the retaining ring is on the top, and constructs a displacement function, then works out the analytical solution of the residual stress under this instance. This conclusion is very valuable in theory engineering.
Cultivating high-quality application-oriented creative talents is the mission statement of general science and engineering colleges and universities. Mathematical thinking and creative thinking capacity is an important component of capacity. Mathematics Competition in Mathematics Education plays a promoting and encouraging role in math education. This… (More)
In this paper we classify finite groups whose nonnormal subgroups are of order p or pq, where p, q are primes. As a by-product, we also classify the finite groups in which all nonnormal subgroups are cyclic.