Performance optimisation illustration

In Brown etal. (2000) Johnson Matthey pursues via five experimental fuel cells, the topic of optimising platinum particle coupling to cathode electrode structure and membrane, while simultaneously improving water removal capability. The resulting cell performances are illustrated in Figure 6.5, reproduced from Brown etal. (2000). 

With a good description of the mass transfer processes occurring in a CDPF now in place, it should be possible to predict the effects of PGM zoning and non-uniform aging on the performance of a CDPF. To illustrate the way in which this model can help in optimising the placement of the PGM washcoat in a CDPF systems, simulations were carried out over the European drive cycle for ... 

A new methodology designed to optimize both the planning of preventive maintenance and the amount of resources needed to perform maintenance in a process plant is presented. The methodology is based on the use of a Montecarlo simulation to evaluate the expected cost of maintenance as well as the expected economic loss, an economical indicator for maintenance performance. The Montecarlo simulation describes different failure modes of equipment and uses the prioritization of maintenance supplied, the availability of labour and spare parts. A Genetic algorithm is used for optimisation. The well-known Tennessee Eastman Plant problem is used to illustrate the results. 

When colour cosmetic pigments are added to O/W or W/O emulsions, the resulting system is referred to as a suspoemulsion. The particles can be in either the internal or external phases, or both, as illustrated in Figure 11.12. An understanding of competitive interactions is also important when optimising the formulation stability and performance of these materials. 

To assess and illustrate the performance of a variety of placement techniques, five methods were applied to the retrofit of steel moment-resisting frames underarange ofseismichazard levels. Two are simple empirical rules, while the other three attempt some form of optimisation. In each case the key constraint is that the total added damping is fixed at the same, constant value, enabling fair comparisons of the schemes performance. 

A multi-objective optimisation methodology is presented for the design of a chemical plant with consideration being given to not only the business incentives, but also the environmental concerns. Application to an illustrative example, illustrated how the substitution of alternative materials can potentially shift the set of trade-off solutions, resulting in step-change improvements in both the economic and life cycle environmental performance. 

Selection of variables for multivariate calibration can be considered an optimisation problem. Well performed variable selection in multivariate analysis is a very relevant step, because the removal of non-informative variables will produce better predicting and simpler models [98]. There are numerous approaches for selection of variables. Using FTIR spectral data Leardi et al [97] have illustrated selection of variables on the basis of a genetic algorithm (GA) [99] combined with PLS for the prediction of the concentrations of three undisclosed additives (A, B and C) in PE films. The exercise aimed at developing an at-line QC tool. The entire data set consisted of 319 spectra with a significant baseline offset (Fig. 7.7). Path length correction was carried out by normalisation to a polymer peak (2662 to 2644 cm ). 

Figure 10 illustrates one possible outcome of applying our optimisation methods to the BPD shown in Figure 8. Specifically, this is the outcome of 28 generational improvements of population size 500 of the process. Note that the new functional requirement (item 5) is now satisfied. In the case of this example the rates for sequencing and parallelising are set so that the Mutate function ensures that considerably more re-sequencing modifications are performed than parallelisation modifications.

A further feature of the structure of the functional domain arises from the central role of the irreducible element in the description of functionality and the definition of that element, as depicted in Fig. C4.4. Due to this view of an engineering project as an optimisation of the balance between cost and revenue, the secondary elements fall into two completely separate categories the elements describing aspects of the cost, and the elements describing aspects of the performance, as already mentioned at the end of Sec. C4.3 and illustrated in Fig. C4.6. 

The results are reported of a study carried out to optimise the development of the continuous mixing process for various NR powders in a twin-screw extruder equipped with co-rotating screws. The effect of various screw elements on the development of properties, including filler dispersion and Mooney viscosity, along the extruder screw is evaluated and a screw configuration optimised for the performance of continuous compounding experiments on different powdered rubber types is illustrated. 11 refs. 

The optimising of a tyre compound to improve reversion resistance is discussed with reference to the use of two new rubber chemicals developed by Flexsys. They are 1,3 bis(citraconimidomethyl benzene) (BMI-MX) and hexamethylene-1,6-bisthiosulphate disodium salt dihydrate (HTS), which are claimed to provide two different ways to improve the thermal ageing resistance of sulphur-based vulcanisates as compared to existing technology. Each functions by uniquely different mechanisms of action and each provides different levels of performance improvements. A comparison is made of HTS and BCI-MXto conventional cure systems and semiefficient cure systems to illustrate the potential benefits of these approaches to address reversion in tyre compounds. 5 refs. 

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