With reviewed papers that have generated several design solutions using the TRIZ solution principles, almost all of them employed AHP as their method for selecting their best design. The remaining number of papers reviewed had not generated a list of design solutions, and were satisfied with one. Vinodh 2014
used the multi-criteria decision making (MCDM) approach, in this case the AHP approach, to select the best design out of the ones generated as a solution to the problem. A hierarchy was constructed and the criteria for the best design were identified. The opinions of experts were collected in order to carry out the pairwise comparison of the criteria, and the weights were calculated accordingly. In order to confirm that the judgement was acceptable, the consistency ratio CR was calculated. Rosli 2013
also used AHP in the selection process of their best design, utilizing the Expert Choice software to aid in this process. They had begun by conducting a survey in order to determine the main and sub-criteria weights that are based on customer's preferences when buying the product they were improving. The pairwise comparisons were done using the author's experiences and their knowledge, and following that they used the Expert Choice Software to rank the design concepts generated. After the design solutions were prioritized, Rosli 2013
went further, by selecting the highest two ranking design solutions that are compatible in design and combining them into one final design of which they were satisfied with. Chakroun 2014
has also applied AHP in order to select their best design, however did not mention how they carried out the pairwise comparison of their criteria. Chen 2012
had likewise used AHP in order to select the best design out of three cases, and after ensuring that the judgement was consistent, they selected one case that ranked the highest based on their identified main and sub-criteria for the best design. One the other hand, in order to determine the optimal solution out of the three which have been generated, Yeh 2010
had three different solutions targeting one problem: to extend the battery service life of a Notebook computer. However, after listing out three solutions derived from the TRIZ solution principles, they combined them into one final design that incorporates all three and thus had ended up one design. They then made an ideal comparative assessment of their final results, and in that way had determined whether it was an optimal solution or not.