Implementazione di modelli di aiuto alle decisioni, basati su tecniche di analisi multi-criteria, come supporto alla programmazione delle strategie e delle azioni sulle reti di trasporto stradale

Assessment is a topic widely discussed in scientific literature, with important influences on many sectors of practical interest. Assessment is part of a decision-making process and it is possible to define the utility of a series of decision-making actions by using a simplified representation of it and according to the goals set. This research work concerns planning in the road transport sector, where assessment is often complex, and it involves many actors and a multidimensional target system. This research work proposes a state of the art of the multi-criteria analysis methods used by scientific literature to support decision-making activities in the road transport sector, together with some applicative case studies carried out during the PhD course. The aim of the study was to set the general topic of the assessment system, standing out the main system components and their interactions. The scientific bibliography has offered a fundamental investigation field on the representation of the interactions made in the assessment process, through the study of mathematical models which allow to translate the decision-making activity using analytic functions. This activity was combined with the application of the decision-making methods to real practical cases, where the decision-making support system helps a subject who has to make a choice in the transport planning sector. In order to provide support to a decision-maker during the assessment of possible intervention strategies for planning the actions of the Plan and of the projects concerning the transport sector, we have represented the structure of a decision-making support system which permits to reach the goals set on the transport and mobility system. In the case studies analysed in this research work, the assessor - according to the methodological approach presented - supports the decision-maker in order to make an assessment based on objective criteria, which reflect the requests of the stakeholders by applying multi-criteria analysis methods. Among the issues which can be dealt with the support of multi-criteria analysis methods, the applicative cases address choice and hierarchization issues. The choice occurs when it is necessary to identify an option among many possible options, able to meet the multiple goals better than the others. The request to provide a hierarchical order instead occurs when it is necessary to schedule a series of interventions for the issues described. Therefore, it is necessary to assign some options which must be all carried out according to a priority order. To overcome the critical issues highlighted by using the multi-criteria analysis methods consolidated in scientific literature, in this research work we proposed a multi-criteria analysis method called MTA (Multi-criteria Trigonometric Approach), aimed at representing the preferable alternative within a decision-making set by using a trigonometric function, in order to create a hierarchy of options according to a goal system. The MTA model represents a first step which paves the way for other research works about the study of shapes of preference function, as well as any development for the implementation of a weight system to be assigned to priority differentiating criteria.