If you often encounter the words "Shi Kaiping", "Special Kaiping" and "Special Kaiping" when searching Japanese patent documents, what do they mean?

Real Kaiping: Careful people will find that the document publication number with the word real Kaiping has a letter U at the end, which actually means practical, that is, "real" means utility model, "open" means openness, and "flat" means equal age, that is, 1988, for example, equal age of 5 years means1. Special Kaiping: "special" means invention (franchise), Kaiping is the same as above. Japanese patent contribution number uses Japanese year and era, and the conversion formula is shown in the following table. If it is an English search interface, the letter S is used in Showa Year and the letter code H is used in Pingan Year. The conversion formula of Japanese year numbers Showa, Taisho, Meiji and Heisei is: N0000= 1 15)A: published patent application /PCT international phase Japanese translation B: published and examined patent application U: published utility model patent application/utility model PCT international phase Japanese translation U 1: unexamined utility model.