This paper,taking the case of machine vision on-line checkout system,introduces the main philosophy and process of designing on-line system based on c/s structure.

For improving the management and working efficiency of agricultural integrated development department in Heilongjiang province, opening the government affairs, and offering more service for farmer, this paper puts forwards the image about constructing the agricultural integrated development online system.

The characteristic of black-box testing of software testing is combined with advantages of online system,how to apply the black-box testing technology to computeraided instruction of program design is discussed and an instance at.

On the basis of the two-dimensional mathematical model~([1]) and the one-dimensional on-line control mathematical model~([2]) for hot delivery and hot charging process of ingot system,a dynamic ingot discharged prediction system was developed successfully and has been used to production process at the end of 2004.

For the requirements of on-line computer control, The one-dimensional mathematical model for the hot transferring and chargingprocess of ingot system has been established by the“Rreformed Tanaka Kou’s Method”that translates the two-dimensional mathematicalmodel of the infinite length type of rectangle into the one-dimensional mathematical model of the infinite length type of cylinder.