Verification matrix

The design verification plan should be constructed so that every design requirement is verified and the simplest way of confirming this is to produce a verification matrix of requirement against verification methods. You need to cover all the requirements, those that can be verified by test, by inspection, by analysis, by simulation or demonstration, or simply by validation of product records. For those requirements to be verified by test, a test specification will need to be produced. The test specification should specify which characteristics are to be measured in terms of parameters and limits and the conditions under which they are to be measured. 

Verification Summary supported by a Verification Matrix, meeting the following objectives ... 

The enterprise seleets the appropriate verification method [inspection, analysis (including mock-ups or simulations), demonstration, or test] for evaluating whether functional and performance requirements, and design characteristic identified in the design architecture, are satisfied. A verification matrix is developed to trace the verification method(s) to requirements of the functional architecture and rcquirements baseline. The enterprise also selects the models or prototypes to be used, which may be partial or complete, and may or may not include humans depending on the purpose and objectives of the verification task. 

Analysis. Here the primary tools are fishbone (cause-and-effect) diagrams that analyze the possible reasons for the problems being considered. FP L will develop a Root Cause Verification Matrix in order to verify that it is tmly working on the root causes of the problems. 

In their broadest application, CRMs are used as controls to verify in a direct comparison the accuracy of the results of a particular measurement parallel with this verification, traceability may be demonstrated. Under conditions demonstrated to be equal for sample and CRM, agreement of results, e.g. as defined above, is proof. Since such possibilities for a direct comparison between samples and a CRM are rare, the user s claims for accuracy and traceability have to be made by inference. Naturally, the use of several CRMs of similar matrix but different analyte content will strengthen the user s inference. Even so, the user stiU has to assess and account for all uncertainties in this comparison of results. These imcertainty calculations must include beyond the common analytical uncertainty budget (i) a component that reflects material matrix effects, (2) a component that reflects differences in the amount of substance determined, (3) the uncertainty of the certified or reference value(s) used, and 4) the uncertainty of the comparison itself AU this information certainly supports the assertion of accuracy in relation to the CRM. However, the requirement of the imbroken chain of comparisons wiU not be formally fulfilled. 

Brandt [200] has extracted tri(nonylphenyl) phosphite (TNPP) from a styrene-butadiene polymer using iso-octane. Brown [211] has reported US extraction of acrylic acid monomer from polyacrylates. Ultrasonication was also shown to be a fast and efficient extraction method for organophosphate ester flame retardants and plasticisers [212]. Greenpeace [213] has recently reported the concentration of phthalate esters in 72 toys (mostly made in China) using shaking and sonication extraction methods. Extraction and analytical procedures were carefully quality controlled. QC procedures and acceptance criteria were based on USEPA method 606 for the analysis of phthalates in water samples [214]. Extraction efficiency was tested by spiking blank matrix and by standard addition to phthalate-containing samples. For removal of fatty acids from the surface of EVA pellets a lmin ultrasonic bath treatment in isopropanol is sufficient [215]. It has been noticed that the experimental ultrasonic extraction conditions are often ill defined and do not allow independent verification. 

Validation of extraction procedures is frequently lacking. A good assessment of quality assurance implies that the extraction recoveries are verified, e.g. by spiking of standard addition. A major drawback is that the spike is not always bound the same way as the compounds of interest. For the development of good extraction methods, materials with an incurred analyte (i.e. bound to the matrix in the same way as the unknown), which is preferably labelled (radioactive labelling would allow verification of the recovery), would be necessary. Such materials not being available, the extraction method used should be validated by other independent methods, e.g. by verification against known samples and by use of a recovery SPC chart. A mere comparison of extraction methods is no validation. 

Verification and/or validation EP14 evaluation matrix effects... 

Analytical chemistry is a critical component of worker safety, re-entry, and other related studies intended to assess the risk to humans during and subsequent to pesticide applications. The analytical aspect takes on added significance when such studies are intended for submission to the U.S. Environmental Protection Agency and/or other regulatory authorities and are thus required to be conducted according to the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA) Good Laboratory Practice (GLP) Standards, or their equivalent. This presentation will address test, control, and reference substance characterization, use-dilution (tank mix) verification, and specimen (exposure matrix sample) analyses from the perspective of GLP Standards requirements. 

The matrix cells do not represent data fields that require numerical values. In first instance they are to be used as a framework for a thought process what needs to be considered and which assessment parameters are affected by certain upset (failures) and how. Where applicable it is possible to give relevant cells a checkmark after due consideration/verification. (For the preparation of checklists, see for example /12/). 

Verification of the proper choice of the enrichment method can be done through recovery studies under varying conditions of the most important parameters, such as amount and quality of the enrichment material, pH of the sample, as well as the amount and quality of analyte and matrix to be enriched. These parameters not only differ based on the chemical behaviour of the analyte, but are also strongly dependent on the matrix to be analysed. 

In order to provide a compliant-ready product, the manufacturer must make sure that the features required for compliance are built into the product. For verification purposes, a requirements traceability matrix should be created to match the appropriate tests for each of these requirements. An excerpt of an actual matrix is show in the following table (Table 2). 

Equations (4.11) and (4.26) have to be identical. Simple verification based on the rules for matrix multiplication ... 

The verification that this inverse matrix is correct is left as an exercise. 

Gutowski, W. (1988). A thermodynamic model of the matrix-reinforcement interface Experimental verification. In Interfaces in Polymer. Ceramic and Metal Matrix Composites (Proc. ICCI-II) (H. Ishida ed.), Elsevier, New York, pp. 735-746. 

Ab initio calculations show [83JA(105) 1760] that the D6/l structure of hexazine corresponds to a very shallow minimum on the PES. Hexazine has been detected experimentally by means of the low-temperature matrix isolation (80AG745) but, according to [83JMS(105)351], this result still requires verification. 

Each of the groups we have introduced so far is compact, i.e., satisfies Definition 3.16. Note that an n x n matrix with complex entries can be thought of as a subset of C . We leave the verification to the reader in Exercise 4.5. 

The verification that the mucin polymer matrix can undergo phase transition prompted the idea that the condensed and hydrated conformations of the... 

Our two command lines below first generate the coefficient matrix A and the right hand side vector b for (1.1), followed by the MATLAB backslash linear equations solver that computes the solution vector x. This is followed by a simple verification of the error inherent in the residual vector A-x — b for our numerical solution x. This error is nearly zero since in MATLAB the number -1.3323e-15 describes the real number —1.3323 10-15. 

Section IA summarizes the molecular model of diffusion of Pace and Datyner (1 2) which proposes that the diffusion of gases in a polymeric matrix is determined by the cooperative main-chain motions of the polymer. In Section IB we report carbon-13 nmr relaxation measurement which show that the diffusion of gases in poly(vinyl chloride) (PVC) - tricresyl phosphate (TCP) systems is controlled by the cooperative motions of the polymer chains. The correlation of the phenomenological diffusion coefficients with the cooperative main-chain motions of the polymer provides an experimental verification for the molecular diffusion model. 

As commonly used in CRS validation, a traceability matrix verifies the relationship between system specifications and testing protocols. The goal of matrixing is to establish the adequacy of protocols. More specifically, all specified system characteristics and functionality should correspond to verification and qualification testing in protocols. 

The ICP was a Perkin-Elmer 3000DV with an AS90 Autosampler, which has an instrument detection limit of about 1 ppb (for most elements) with a linear calibration up to 100 ppm (for most elements). Solid samples were prepared via microwave digestion in concentrated nitric and hydrochloric acids, then diluted to volume. The ICP was calibrated and verified with two independent, certified standard sets. Spikes and dilutions were done for each batch of samples to check for and/or mitigate any matrix effects. The ICP process ran a constant pump rate of 1.5 mL/min for all samples and standards during analysis. A 3 mL/min rinse and initial sample flush were used to switch between each sample and standard. The plasma was run at 1450 W with argon flow. Trace metal-grade (sub-ppb) acids and two independently NIST-certified calibration standard sets were used for calibration and method verification. 

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