Accuracy, significance

A Task Group carries out the peer review. The Task Group members serve as individual scientists, not as representatives of any organization, government, or industry. Their function is to evaluate the accuracy, significance, and relevance of the information in the document and to assess the health and environmental risks from exposure to the chemical. The principles, procedures, and scientific criteria that guide the evaluations are described in the preamble to the EHC monographs. 

There are empirical relationships which relate alloy content to T, but these are not usually applicable to all types of Ti alloy and can suffer from a lack of accuracy. Significantly, there are no such relationships which can be generally used for predicting the amount of a and 13 in commercial alloys as a function of temperature and composition and little work has been undertaken to quantitatively understand the partitioning of elements between the a and 0 phases. 

It has recently been shown that computational chemistry methods can provide the accuracy required to reliably solve complex environmental problems but accuracy significantly increases the computational demands. Examples of how computational chemistry is being used to impact environmental science include the following ... 

By performing a number of conditioning cycles the polymer network is warmed up and the repeat accuracy significantly increases. The conditioning process typically requires between six and thirty swelling cycles (Richter et al. 2004b). A detailed description of an initial gel conditioning procedure of a sensor is provided in Sect. 5.2.4. 

All three issues can be solved with analytic derivative techniques, as they provide results of high accuracy, significantly reduce the computational cost (for example, the cost is independent of the number of perturbations for gradients), and are easily extended to formally imaginary perturbations. 

Here T,(x) is the stored exact value, Ax is the deviation of the queried point from the stored point, and d YJdxj and d YJdx dxj are the first-order and second-order local sensitivity coefficients, respectively. There are several efficient numerical methods for the calculation of the first-order local sensitivity coefficients (see Sect. 5.2). The second-order local sensitivity coefficients can be calculated from the first-order coefficients using a finite-difference approximation. The Taylor series approximations have the general disadvantage that the accuracy significantly decreases further from the central point. 

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