Measurement capability

The way of measuring capability is to carry out a capability study and calculate a capability index. There are two commonly used process capability indices, Cp and Cpk. In both cases, it is assumed the data is adequately represented by the Normal distribution (see Appendix I). 

Practical applications of SR-TXRF currently focus on fast mapping of wafers up to a diameter of 300 mm and reference measurement capabilities in the range of 10 -10 atoms cm [4.58]... 

Release waves for the elastic-plastic regime are dominated by the strength effect and the viscoplastic deformations. Here again, quantitative study of the release waves requires the best of measurement capability. The work of Asay et al. on release of aluminum as well as reloading, shown in Fig. 2.11, demonstrates the power of the technique. Early work by Curran [63D03] shows that limited time-resolution detectors can give a first-order description of the existence of elastic-plastic behavior on release. 

The standard requires the supplier to use equipment in a manner which ensures that measurement uncertainty is known and is consistent with the required measurement capability. 

On occasions you may require a measurement capability that exceeds the known state of the art, such accuracy and precision that no available device can achieve. If under contract to a customer you should inform your customer of this situation so that you can negotiate the measures needed to develop the technology required. (See Part 2 Chapter 2 on Identifying new measurement capabilities.)... 

It should be recognized that, in some cases, it is not difficult to set up a traceable measurement system. The best examples of this are in physical metrology where traceability is often based on direct measurements of the SI units. There is also general agreement that a similar SI fink is highly desirable in the case of chemical measurements, but, for a variety of reasons, direct chemical traceability is difficult to achieve in most of the analytical chemistry applications. Only a very few analytical chemistry procedures exhibit a direct measurement capability that allows the set-up of a traceable measurement pathway such as in physical metrology measurements most of these procedures have been accepted as primary methods if carried out under certain constraints (CCQM 1998). 

A freeze drying plant should have as a minimum the following measuring capabilities ... 

The emergence of sensitive and affordable array detectors in 1980s and 1990s has also improved measurement capability in the UV-vis. Commercially available UV-vis instrumentation with photodiode-array (PDA) detectors appeared in the mid-1980s. This made it possible to produce a UV-vis spectrophotometer... 

Demonstrated measurement capability, to produce reference value... 

The experimental configuration in Figure 4.1 does not provide in situ capability for sono-, photo- and microwave-induced homogeneous catalysis. The chemistry occurring in the fluid elements of an irradiated or sonicated CSTR are not similar to the fluid elements in the recycle stream and sample cells. However, Figure 4.1 maintains the potential for on-line measurement capability, particularly for product, and for some side-products. The issue concerning intermediates is more complex. 

Nordmeyer, T., and K. A. Prather, Real-Time Measurement Capabilities Using Aerosol Time-of-Flight Mass Spectrometry, Anal. Chem., 66, 3540-3542 (1994). 

Sandholm, S., S. Smyth, R. Bai, and J. Bradshaw, Recent and Future Improvements in Two-Photon Laser-Induced Fluorescence NO Measurement Capabilities, J. Geophys. Res., 102, 28651-28661 (1997). 

The IMEP rounds involve laboratories are from all around the world of different metrological function and experience. Measuring the same quantity in the same sample yields evidence of measurement capability. Complete anonymity of laboratories is preserved, and although the program provides analysis of the results in the form of tables and graphs, laboratories draw their own conclusions about the accuracy of their results. 

Provide confidence in, and knowledge of the measurement capabilities of participating laboratories for all users, including the regulatory and accreditation communities,... 

The [calibration system] controls, calibrates, and maintains inspection, measuring, and test equipment to demonstrate the conformance of the product to the specified requirements. Equipment is used in such a manner so as to ensure that measurement uncertainty is known and is consistent with the required measurement capability. The measurements made are identified, the accuracy is stated, and the appropriate inspection, measuring, and test equipment is used. 

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