DEVELOPMENTS OF DESIGNING METHOED OF CONTROL CHART TO ENHANCE DETECTION POWER IN HIGH-YIELD PROCESSES

在本研究项目中，主要探讨了两个研究课题，并在2002年至2004年期间由太田教授和Kusukawa研究助理获得了研究结果。1.控制图的设计，以检测灵敏的小或中等变化向任何方向，这表明过程恶化和过程改进，在过程中的平均值从小尺寸的子组，过程分数缺陷或过程缺陷率在高产量过程中，几乎实现了上述质量特性的I型错误的规定值。我们提出的控制图作为Shewhart型图如X^^-R图、p图和c图的替代控制图将非常有用（见参考文献1、2、3、5、6、7、9、11、12和13）。2.控制图的经济设计是在上述研究课题1中进行的。以在各种过程情况下，例如过程故障率随时间变化的动态过程中，最大化每单位时间的过程周期的系统利润或最小化每单位时间的过程周期的系统成本。当需要经济地运行高产量过程时，我们提出的经济设计方法将非常有用，通过使用我们在上述研究主题1中提出的控制图。(See参考文献4、8和10）。作为今后的研究工作，可以在文献1和文献6的基础上，设计CCC-r图和文献13的EWMA_图的综合EWMA图<CCC-r>。由时间序列资料所建构之合成EWMA图较合成CS图能更灵敏地监控制程不良率。作为进一步的研究工作，在参考文献4、8和10的基础上，可以开发动态过程下综合EWMA图的经济设计。

In this research project, two study subjects have been mainly approached and the research findings have been obtained between 2002 and 2004 by Professor Ohta and Research Associate Kusukawa. 1. Design of control chart to detect sensitively small or moderate shifts toward any directions, which indicate the process deterioration and the process improvement, in the process mean obtained from small size of subgroups, the process fraction defectives or the process defect rate in high-yield processes and actualize almost a specified value of type I error of quality characteristics mentioned above. Our proposed control charts would be useful highly as alternative control charts of the Shewhart types charts such as X^^-R chart, p chart and c chart (See REFERENCES 1, 2, 3, 5, 6, 7, 9, 11, 12 and 13.). 2. Economic design of control chart developed in above study subject 1. to maximize the system profit per unit time of process cycle or to minimize system cost per unit time of process cycle under various process situations such as dynamic process where the process failure rate is varying over time. Our proposed-economic designing methods would be useful highly when it is required to run a high-yield process economically by using our proposed control charts in above study subject 1.. (See REFERENCES 4, 8 and 10.). As the future Research work, based on REFERENCES 1 and 6, the Synthetic EWMA chart that is integration of the CCC-r chart and the EWMA_<CCC-r> chart in REFERENCE 13 could be designed. It is expected that the Synthetic EWMA chart constructed from time-series data would be more sensitive to monitor the process defective rate than the Synthetic CS chart. As the further future Research work, based on REFERENCES 4, 8 and 10, an economic design of the Synthetic EWMA chart under dynamic process could be developed.