Process-aware information systems support business operations as they are typically defined in a normative process model. Often these systems do not directly execute the process model, but provide the flexibility to deviate from the normative model. This paper proposes a method for monitoring control-flow deviations during process execution. Our contribution is a formal technique to derive moni...

Simultaneously monitoring two or more quality characteristics depends on the development of more specific statistical tools to detect, identify and analyze the major causes of variability that affect the behavior of the production process. The multivariate control charts represent one of these emerging statistical techniques successfully used to monitor simultaneously several correlated charact...

Control charts are themost extensively used technique to detect the presence of special cause variations in processes. They can be classified intomemory andmemoryless control charts. Cumulative sum and exponentially weightedmoving average control charts are memory-type control charts as their control structures are developed in such a way that the past information is not ignored as it is done i...

control limits of Zhang (1984) and Wade and Woodall (1993). It has been observed that the proposed charts perform superior, in terms of discriminatory power, as compared to the above mentioned counterparts, depending upon the correlation structure among the auxiliary characteristics and the quality characteristic of interest. The said superiority zone of the correlation structures, favoring the...

An ultrasonic sensor has been developed to monitor photoresist processing in situ during semiconductor manufacturing. Photoresist development, pre-exposure bake, and postexposure bake were monitored for the Shipley 1800 series I-line resists, and the pre-exposure bake of Shipley APEX-E deep-uv (DUV) resist was monitored as well. Development monitoring was achieved by measuring thickness changes...

The Shewhart and the Bonferroni-adjustment S control charts are usually applied to monitor the standard deviation of a quality characteristic. The control limits of these charts are constructed using approximately the normal distribution in case that the standard deviation parameter is known or unknown. In this paper, we establish a new S chart that is based approximately on the normal distribu...

Estimates of the percentage of industrial process controllers with performance problems are surprisingly high – various studies indicate that anywhere from 66% to 80% of controllers are not performing as well as they should. These controllers can have a significant detrimental effect on plant profitability, both in increased product variance and increased reaction times. In addition, the regula...

Statistical process control is an excellent quality assurance tool to improve the quality of manufacture and ultimately scores on end-customer satisfaction. SPC uses process monitoring charts to record the key quality characteristics (KQCs) of the component in manufacture. This paper elaborates on one such KQC of the manufacturing of a connecting rod of an internal combustion engine. Here th...