ISO 28593:2017, Acceptance sampling procedures by attribures - Accept-zero sampling system based on creidit principle for controlling (replace ISO 21247:2005)
ISO 28594:2017, Combined accept-zero sampling systems and process control procedures for product acceptance (replace ISO 18414:2006)
字碼、樣本大小、excel 可以自動查詢、不難。困難點在於如何推進。
AQL 精神，轉換準則，
Log book 紀錄簿，自動查字碼，決定樣本大小。計數型
計量型 F = S[sup]2[/sup]/σ[sup]2[/sup]
馬可夫鏈 (矩陣)
工業 4.0 靠設備，機台設備維護保養，
工業 4.0 品管人的角色？
人不再作執行業務，改做決策業務。
封測機台，晶圓切割成晶粒（晶片）
chip-out 裂痕產生，如何克服。
打線封裝，ESD 電性測試。Open short OK，銲腳。
自動化機台，切九刀、第十刀減慢速度，影像檢驗。慢刀、機台休息。
ISO 28593:2017
6 Credit principle
The unifying concept behind the sampling schemes in this International Standard is the credit principle. It is assumed that a supplier submits for inspection a continuing sequence of lots of items. Each lot may be of any size.
NOTE. For short series of lots or for an isolated lot, the AOQL protection is still valid, in the sense that the expected outgoing quality will still be no worse than the AOQL. However, the realized average outgoing quality may well be worse than the AOQL, although the chance of this happening decreases as the series gets longer. Moreover, the supplier does not benefit to the same extent from an accumulation of credit and the resulting reduction in inspection costs.
At the start of inspection, the credit is set to zero. The appropriate sample size for each lot is determined from a formula involving the AOQL, the lot size and the credit. A random sample of this size is selected and inspected. If the first lot fails to meet the acceptance criterion, the credit remains at zero. Otherwise, the credit is increased by the lot size. The process is repeated with successive lots, with credit increasing by the size of accepted lots until a lot is non-accepted, at which point the credit is reset to zero and a new sequence is started.
By this means, a supplier who submits lots of consistently high quality is rewarded by smaller sample sizes and therefore lower inspection costs, while the required AOQL is still guaranteed.
Where items are supplied by a number of suppliers, this International Standard shall be applied to the lots from each supplier separately. Suppliers shall therefore have their own individual credit records.