Calculation and selection of sequentially truncated test scheme

The method for calculating the two types of risk's real value under sequential test scheme was researched, and software for calculating the truncation scheme of test was programed. Then test scheme was analyzed and the relationship between truncated sequential test and fixed number test was studied. Two methods to select the test scheme in the specimen number limited conditions was put forward, the first method is to modest relaxation of risk requirements, and the second is to adjust the test's reception line and reject line which could decrease the maximum required number of trials and keep the two types of risk unchanged. These two methods could determine the testing program flexibly under the specific test requirements, which allow the maximum required number of trials decrease about 30% with the two types of risk or minimum required number of trials increase less than 10%.