Page 222 - Materials Chemistry, Second Edition
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220            10. Advancing life cycle sustainability assessment using multiple criteria decision making

                         method seems to be a more appropriate technique due to its simplicity and pictorial
                         representation of relationships.
                  Step 6: Consistency of inputs on indicators: Partial check for preferential interdependence
                         must be checked. In case there exists dependency within the indicators, indicators
                         selection can be revisited in Step 1. For example, combine multiple indicators with
                         dependence or break dependent indicators into multiple subindicators. Similarly,
                         inputs must be checked for asymmetry, transitivity, and comparability, and if
                         negative values of indicators exist, then normalization of data is appropriate.
                  Step 7: Selection of weighting methods for indicators: Different weighting method produce
                         different results. Therefore, use of multiple weighting methods is recommended
                         and carrying out sensitivity on weights.
                  Step 8: Apply MADM method using the weights for indicators and impacts (Scores) from
                         Step 3 to obtain integrated final impact.
                  Step 9: Uncertainty and sensitivity analysis: As there are number of sources of uncertainty
                         in LCSA based MADM approach, detailed uncertainty and sensitivity analysis
                         should be performed.
                 Step 10: Interpretation of results from the analysis: MADM results are usually obtained as
                         single scores and hence need further interpretation. This is an essential step where
                         the final scores should be validated with the data and methods used for LCSA.
                 Step 11: Report the final aggregated impact with recommendations and share the results
                         with stakeholders for feedback.



                                                 10.7 Conclusions


                   LCSA is a fast-developing field, and numerous efforts are being made to refine the frame-
                 work and associated methods used for sustainability assessment. In this work, we have taken
                 stock of using different MADM methods for LCSA. The basic structure of LCSA is described
                 in detail and highlighted the suitability of MADM methods in integrating indicators
                 with LCSA.
                   The review of applications of MADM for LCSA showed that there are numerous chal-
                 lenges of applying MADM to LCSA. The challenges of MADM application are discussed
                 in detail. A framework is proposed for carrying out LCSA using MADM. The framework
                 is also able to highlight tackling of challenges in integrating MCDA with LCSA, such as, dom-
                 inating alternatives, choice of appropriate MADM method, consistency of inputs on indica-
                 tors, selection of weighting methods for indicators, and uncertainty and sensitivity analysis.
                   One of the critical issues identified is the choice of MADM method for LCSA. It is
                 recommended that there is no unique suitable MADM method for LCSA, and hence,
                 it is suggested to define scenarios for the given decision-making situation in LCSA. Once
                 the scenarios are articulated, accordingly, more refined weights can be given to the indicators.
                 Using this set of weights, if more than one MADM method ranks the same alternative as most
                 preferred then such an alternative can be conclusively identified as more sustainable than the
                 other one based on LCSA coupled with MADM approach. In addition, there exist many meth-
                 odological uncertainties while implementing LCSA (choice of assessment methods, data
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