Define, measure, analyze, improve, and

The Six Sigma approach is composed by five steps, i.e. the DMAIC algorithm (Fig. 1) Define, Measure, Analyze, Improve and Control. 

DMIAC Define, Measure, Analyze, Improve, and Control. A process for implementing supply chain changes associated with the Six Sigma improvement process. (A foundation for operational excellence, Supply Chain Management Review, March/April 2003)... 

DMAIC Define, Measure, Analyze, Improve, and Control... 

Six sigma Six sigma is one of the more recent popular approaches to QA that is based on a tight statistical approach to the production of a product. The name arises from a desire to limit the tolerance of a product to plus or minus six standard deviations and thus have only 3.4 defects per million. (This is the fraction outside - - 4.5 standard deviations from the mean the method allows for some measurement uncertainty.) In order for the statistics to hold, the system must be in statistical control and the defects must be random and normally distributed. There is a heavy reliance on control charts and the system is built around what to do if there is evidence for nonconformity. For a nonconforming product six sigma institutes an approach with the acronym DMAIC — define, measure, analyze, improve, control. This has been implemented in some organizations, such as pharmaceutical companies, which produce large volumes of chemicals. However, strict statistical control of chemical products is not always easy, and considerations of the measurement process also needs to be taken into account. 

Some of the Six Sigma models are DMAIC (Define, Measure, Analyze, Improve, Control), which is used to improve the existing process, and DMADV (Define, Measure, Analyze, Design, Verify), which is used to employ the new products. 

The quality improvement project or action starts with the identification of an improvement opportunity which is based on measures of quality losses and/or on comparisons against organizations recognized as leaders in a particular field. The opportunity for improvement is defined and the process involved is evaluated by analyzing data and facts. The objectives for improvement are introduced. 

A quality management system s process should follow a standard Six Sigma process improvement life cycle that includes the following steps define (process and metrics), measure and control (identify problems and issues), analyze (analyze problems and issues), and improve (implement) circling back to measure and control [11]. An example of a process improvement life cycle can be seen in Figure 9. 

As described in detail by Rath and Strong (2000), an iterative five-step procedure is followed to progressively improve product quality. The five steps are (a) Define, (b) Measure, (c) Analyze, (d) Improve, and (e) Control, referred to by the acronym, DMAIC ... 

After the earthquake in Vrancha in 1987, reassessment of the seismic impact was done, and number of measures for improvement the seismic stability of civil constructions and equipment was performed. After the year 1989, IAEA Project (BUL/9/012) was initiated. Within this project additional investigations of the seismic impact on the site were executed, considering also the effect of the local earthquakes. New seismic characteristics of the site were defined SL — 1 = 0.1 g (10 y ) and SL — 2 = 0.2 g (lO " y ). Using the new characteristics, new response spectra were developed (defined) and behaviour of all the components, important to safety, was analyzed under this impact. 

Slope/bias correction This method, which is really a postprocessing of model outputs, is one of the simplest improvement methods, and can be quite effective in cases where temporal shifts in analyzer response are expected [105]. However, when used, it should be accompanied by a well-defined sampling and measurement protocol, in order to generate a sufficiently large population of time-localized standards that can be used to determine stable estimates of slope and bias correction factors. 

An analytical procedure has been proposed for precise uranium isotope ratio measurements in a thin uranium layer on a biological surface by LA-ICP-MS using a cooled laser ablation chamber.125 One drop of uranium isotope standard reference materials NIST, 350, NIST 930, of our isotopic laboratory standard CCLU 500 (20p.l, U concentration 200 ng 1) and of uranium with natural isotopic pattern were deposited on the leaf surface and analyzed by LA-ICP-MS at well defined laser crater diameters of 10, 15, 25 and 50 p.m. A precision for measurements of isotope ratios in the range of 2.1-1.0% for 235U/238U in selected isotope standards was observed whereby the precision and the accuracy of isotope ratios compared to the non-cooled laser ablation chamber was improved.125... 

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