Abstract

International audience; Urban development is a critical issue that many cities are facing, due to the demography growth which results from the economic attractiveness of the urban centers. Based on common standards such as the Urban Development Plans, some projects for transportation systems renewal are progressively launched. In order to allow social cohesion, especially by providing travelers with services which may allow to better organize the transport, it is necessary to structure the transportation system according to sustainability requirements. This paper examines an integrated approach for assessing the sustainability of the current transportation system design, based on a policy making problem, aiming at providing decision makers with a framework allowing them to choose the most eco-responsible policy amongst many alternatives. Since the sustainability indicators may conflict each other, in order to better take into account the requirements of the whole transportation system in its design phase, a system-based approach has been adopted to characterize the complex structure of these indicators. A general methodology for their elicitation is proposed, using a process-object methodology and based on surveys from recent research on sustainable transportation, along with eco-design principles, in order to take into account urban transport priorities, sustainability challenges and the analysis of the whole lifecycle of the transport infrastructure and equipment. To validate this proposal, a multi-criteria decision method, allowing subjectivity, uncertainty, incomplete judgments and group consensus is then performed, based on a case study which shows the flexibility of fuzzy analytical hierarchy process for such assessment.

Abstract

This paper describes a methodology for the application of Multi-Criteria Decision-Making (MCDM) on the technology selection for emissions reduction from shipping under uncertainties and incomplete information. Nine criteria in four aspects, including technological (maturity), economic (capital cost and operation cost), environmental (effects of SO "sub"x"/sub", NO "sub"x"/sub", GHG, and PM reduction), and social-political aspects (government support and social acceptability), were used for the sustainability assessment. The study aims at developing the methodology for technology selection for emissions reduction from shipping by combining Fuzzy Analytic Hierarchy Process (AHP) and VIKOR. Fuzzy AHP was used to determine the weights of the evaluation criteria and the relative performance of the alternatives with respect to each evaluation criterion, and VIKOR was used to prioritize the alternative technologies. The two methods of VIKOR and the traditional AHP were combined to validate the proposed methodology. Three alternative technologies of low sulphur fuel, scrubber and LNG were studied using the proposed model, and the results indicate that the proposed methodology is capable of assisting the decision-makers to select the most sustainable technology for emissions reduction from shipping under uncertainties and incomplete information.

Abstract

Narrow trenches are a common technique for the installation of utility pipelines of small diameter. Theexcavated soil is not always appropriate as landfill and, in those cases, an appropriate soil from some-where else (ex. a borrow pit or another construction site) should be used instead (classical solution, CS).Another common solution is to use a controlled low-strength (cementitious) material (CLSM) as backfillinstead of compacted soil. However, both solutions lead to increased raw material consumption, wastegeneration, need for transportation, and CO2emissions. In an attempt to address these issues, researchersdeveloped an eco-trench (ECO) that reuses the excavated soil of narrow trenches to produce a controlledlow-strength material to be used as landfill. Although technically viable, the sustainability of this solutionversus the traditional solution has not been properly addressed. Hence, this paper aims to develop amethod for the sustainability assessment of trenches. The Sustainability Index of Trenches (SIT), based onthe MIVES decision-making method, enables the assessment and prioritisation of different types oftrenches according to sustainability criteria. Criteria, indicators, weights and value functions were spe-cifically defined based on seminars with experts in thefield of utility services and construction. A casestudy was performed in which four types of trenches (CS, CS with recycling CSþR, CLSM and ECO) wereassessed and prioritised according to SIT. ECO resulted in the most sustainable alternative with a SIT of0.80 out of 1 followed by CSþR, CS and CLSM with SITs of 0.63, 0.40 and 0.38 respectively. The sensitivityanalysis showed consistent results in different scenarios. Thesefindings demonstrate the capability andreliability of SIT as a decision-making tool for the evaluation of the sustainability of different constructionprocesses for trenches and the prioritisation of the most suitable solution for different situations Peer Reviewed Document type: Article

Abstract

Pavement maintenance is essential to prevent the deterioration of asset value and to satisfy the expectations of all stakeholders (objectives). However, the budgets are often insufficient to keep the road pavement at optimum levels. Therefore, a decision making process ought to be used for prioritizing different maintenance activities in order to achieve pre-defined goals by optimizing the use of the available budget. One of the biggest difficulties in multiobjective optimization method is the large number of the feasible solutions (Pareto optimal set or its approximation), which makes it hard for the Decision Maker to select the best solution."br/""br/"To support interaction with the decision maker for identifying the best combination of maintenance actions, this paper proposes a new methodology named “Interactive Multiobjective Optimization-Dominance Rough Set Approach” (IMO-DRSA), using a decision-rule preference model."br/""br/"The preference information, obtained by the Decision Maker (DM) during the course of the interaction, is processed using the Dominance-based Rough Set Approach in order to achieve a decision model expressed in terms of easily understandable “if ….then …” decision rules. This approach makes possible an interaction between the analyst and the decision maker and helps the decision maker to classify maintenance options and allocate limited funds according to predefined objectives (quantitative or qualitative). An application of the proposed methodology to road pavements of an Italian urban sub-network is presented. Document type: Article

Abstract

In any public service development decision, it is essential to reach the stakeholders&rsquo agreement to gain a sustainable result, which is accepted by all involved groups. In case this criterion is violated, the impact of the development will be less than expected due to the resistance of one group or another. Concerning public urban transport decisions, the lack of consensus might cause lower utilisation of public vehicles, thus more severe environmental damage, traffic problems and negative economic impacts. This paper aims to introduce a decision support procedure (applying the current MCDM techniques Fuzzy and Interval AHP) which is capable of analysing and creating consensus among different stakeholder participants in a transport development problem. The combined application of FAHP and IAHP ensures that the consensus creation is not only based on an automated computation process (just as in IAHP) but also on the consideration of specific group interests. Thus, the decision makers have the liberty to express their preferences in urban planning, along with the consideration of numerical results. The procedure has been tested in a real public transport improvement decision as a follow-up project, in an emerging city, Mersin, Turkey. Results show that by the application of the proposed techniques, decision-makers can be more aware of the conflicts of interests among the involved groups, and they can pay more attention to possible violations. Document type: Article